/*
* __ckpt_verify --
* Diagnostic code, confirm we get what we expect in the checkpoint array.
*/
static int
__ckpt_verify(WT_SESSION_IMPL *session, WT_CKPT *ckptbase)
{
WT_CKPT *ckpt;
/*
* Fast check that we're seeing what we expect to see: some number of
* checkpoints to add, delete or ignore, terminated by a new checkpoint.
*/
WT_CKPT_FOREACH(ckptbase, ckpt)
switch (ckpt->flags) {
case 0:
case WT_CKPT_DELETE:
case WT_CKPT_DELETE | WT_CKPT_FAKE:
case WT_CKPT_FAKE:
break;
case WT_CKPT_ADD:
if (ckpt[1].name == NULL)
break;
/* FALLTHROUGH */
default:
return (
__wt_illegal_value(session, "checkpoint array"));
}
return (0);
}
/*
* __ckpt_verify --
* Diagnostic code, confirm we get what we expect in the checkpoint array.
*/
static int
__ckpt_verify(WT_SESSION_IMPL *session, WT_CKPT *ckptbase)
{
WT_CKPT *ckpt;
/*
* Fast check that we're seeing what we expect to see: some number of
* checkpoints to add, delete or ignore, terminated by a new checkpoint.
*/
WT_CKPT_FOREACH(ckptbase, ckpt)
switch (ckpt->flags) {
case 0:
case WT_CKPT_DELETE:
case WT_CKPT_DELETE | WT_CKPT_FAKE:
case WT_CKPT_FAKE:
break;
case WT_CKPT_ADD:
if (ckpt[1].name == NULL)
break;
/* FALLTHROUGH */
default:
/*
* Don't convert to WT_ILLEGAL_VALUE, it won't compile
* on some gcc compilers because they don't understand
* FALLTHROUGH as part of a macro.
*/
return (__wt_illegal_value(session, ckpt->flags));
}
return (0);
}
/*
* __wt_block_read_off --
* Read an addr/size pair referenced block into a buffer.
*/
int
__wt_block_read_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
WT_ITEM *buf, wt_off_t offset, uint32_t size, uint32_t cksum)
{
WT_BLOCK_HEADER *blk;
size_t bufsize;
uint32_t page_cksum;
WT_RET(__wt_verbose(session, WT_VERB_READ,
"off %" PRIuMAX ", size %" PRIu32 ", cksum %" PRIu32,
(uintmax_t)offset, size, cksum));
WT_STAT_FAST_CONN_INCR(session, block_read);
WT_STAT_FAST_CONN_INCRV(session, block_byte_read, size);
/*
* Grow the buffer as necessary and read the block. Buffers should be
* aligned for reading, but there are lots of buffers (for example, file
* cursors have two buffers each, key and value), and it's difficult to
* be sure we've found all of them. If the buffer isn't aligned, it's
* an easy fix: set the flag and guarantee we reallocate it. (Most of
* the time on reads, the buffer memory has not yet been allocated, so
* we're not adding any additional processing time.)
*/
if (F_ISSET(buf, WT_ITEM_ALIGNED))
bufsize = size;
else {
F_SET(buf, WT_ITEM_ALIGNED);
bufsize = WT_MAX(size, buf->memsize + 10);
}
WT_RET(__wt_buf_init(session, buf, bufsize));
WT_RET(__wt_read(session, block->fh, offset, size, buf->mem));
buf->size = size;
blk = WT_BLOCK_HEADER_REF(buf->mem);
page_cksum = blk->cksum;
if (page_cksum == cksum) {
blk->cksum = 0;
page_cksum = __wt_cksum(buf->mem,
F_ISSET(blk, WT_BLOCK_DATA_CKSUM) ?
size : WT_BLOCK_COMPRESS_SKIP);
if (page_cksum == cksum)
return (0);
}
if (!F_ISSET(session, WT_SESSION_SALVAGE_CORRUPT_OK))
__wt_errx(session,
"read checksum error [%" PRIu32 "B @ %" PRIuMAX ", %"
PRIu32 " != %" PRIu32 "]",
size, (uintmax_t)offset, cksum, page_cksum);
/* Panic if a checksum fails during an ordinary read. */
return (block->verify ||
F_ISSET(session, WT_SESSION_SALVAGE_CORRUPT_OK) ?
WT_ERROR : __wt_illegal_value(session, block->name));
}
/*
* __wt_turtle_read --
* Read the turtle file.
*/
int
__wt_turtle_read(WT_SESSION_IMPL *session, const char *key, char **valuep)
{
FILE *fp;
WT_DECL_ITEM(buf);
WT_DECL_RET;
int match;
char *path;
*valuep = NULL;
fp = NULL;
path = NULL;
/*
* Open the turtle file; there's one case where we won't find the turtle
* file, yet still succeed. We create the metadata file before creating
* the turtle file, and that means returning the default configuration
* string for the metadata file.
*/
WT_RET(__wt_filename(session, WT_METADATA_TURTLE, &path));
if ((fp = fopen(path, "r")) == NULL)
ret = __wt_errno();
__wt_free(session, path);
if (fp == NULL)
return (strcmp(key, WT_METAFILE_URI) == 0 ?
__metadata_config(session, valuep) : ret);
/* Search for the key. */
WT_ERR(__wt_scr_alloc(session, 512, &buf));
for (match = 0;;) {
WT_ERR(__wt_getline(session, buf, fp));
if (buf->size == 0)
WT_ERR(WT_NOTFOUND);
if (strcmp(key, buf->data) == 0)
match = 1;
/* Key matched: read the subsequent line for the value. */
WT_ERR(__wt_getline(session, buf, fp));
if (buf->size == 0)
WT_ERR(__wt_illegal_value(session, WT_METADATA_TURTLE));
if (match)
break;
}
/* Copy the value for the caller. */
WT_ERR(__wt_strdup(session, buf->data, valuep));
err: if (fp != NULL)
WT_TRET(fclose(fp) == 0 ? 0 : __wt_errno());
__wt_scr_free(&buf);
return (ret);
}
/*
* __wt_meta_turtle_read --
* Read the turtle file.
*/
int
__wt_meta_turtle_read(
WT_SESSION_IMPL *session, const char *key, const char **valuep)
{
FILE *fp;
WT_DECL_RET;
const char *path;
char *p, line[1024];
fp = NULL;
path = NULL;
/* Open the turtle file. */
WT_RET(__wt_filename(session, WT_METADATA_TURTLE, &path));
WT_ERR_TEST((fp = fopen(path, "r")) == NULL, WT_NOTFOUND);
/* Search for the key. */
ret = WT_NOTFOUND;
while (fgets(line, sizeof(line), fp) != NULL) {
if ((p = strchr(line, '\n')) == NULL)
goto format;
*p = '\0';
if (strcmp(key, line) == 0)
ret = 0;
/* Key matched: read the subsequent line for the value. */
if (fgets(line, sizeof(line), fp) == NULL)
goto format;
if ((p = strchr(line, '\n')) == NULL)
goto format;
*p = '\0';
if (ret == 0)
break;
}
/* Check for an I/O error. */
if (ferror(fp))
WT_ERR(__wt_errno());
WT_ERR(ret);
/* Successful: copy the value for the caller. */
WT_ERR(__wt_strdup(session, line, valuep));
if (0) {
format: return (__wt_illegal_value(session, WT_METADATA_TURTLE));
}
err: if (fp != NULL)
WT_TRET(fclose(fp));
__wt_free(session, path);
return (ret);
}
/*
* __wt_turtle_read --
* Read the turtle file.
*/
int
__wt_turtle_read(WT_SESSION_IMPL *session, const char *key, char **valuep)
{
WT_DECL_ITEM(buf);
WT_DECL_RET;
WT_FSTREAM *fs;
bool exist, match;
*valuep = NULL;
/*
* Open the turtle file; there's one case where we won't find the turtle
* file, yet still succeed. We create the metadata file before creating
* the turtle file, and that means returning the default configuration
* string for the metadata file.
*/
WT_RET(__wt_fs_exist(session, WT_METADATA_TURTLE, &exist));
if (!exist)
return (strcmp(key, WT_METAFILE_URI) == 0 ?
__metadata_config(session, valuep) : WT_NOTFOUND);
WT_RET(__wt_fopen(session, WT_METADATA_TURTLE, 0, WT_STREAM_READ, &fs));
/* Search for the key. */
WT_ERR(__wt_scr_alloc(session, 512, &buf));
for (match = false;;) {
WT_ERR(__wt_getline(session, fs, buf));
if (buf->size == 0)
WT_ERR(WT_NOTFOUND);
if (strcmp(key, buf->data) == 0)
match = true;
/* Key matched: read the subsequent line for the value. */
WT_ERR(__wt_getline(session, fs, buf));
if (buf->size == 0)
WT_ERR(__wt_illegal_value(session, WT_METADATA_TURTLE));
if (match)
break;
}
/* Copy the value for the caller. */
WT_ERR(__wt_strdup(session, buf->data, valuep));
err: WT_TRET(__wt_fclose(session, &fs));
__wt_scr_free(session, &buf);
if (ret != 0)
__wt_free(session, *valuep);
return (ret);
}
/*
* __wt_metadata_load_backup --
* Load the contents of any hot backup file.
*/
int
__wt_metadata_load_backup(WT_SESSION_IMPL *session)
{
FILE *fp;
WT_DECL_ITEM(key);
WT_DECL_ITEM(value);
WT_DECL_RET;
const char *path;
fp = NULL;
path = NULL;
/* Look for a hot backup file: if we find it, load it. */
WT_RET(__wt_filename(session, WT_METADATA_BACKUP, &path));
if ((fp = fopen(path, "r")) == NULL) {
__wt_free(session, path);
return (0);
}
/* Read line pairs and load them into the metadata file. */
WT_ERR(__wt_scr_alloc(session, 512, &key));
WT_ERR(__wt_scr_alloc(session, 512, &value));
for (;;) {
WT_ERR(__wt_getline(session, key, fp));
if (key->size == 0)
break;
WT_ERR(__wt_getline(session, value, fp));
if (value->size == 0)
WT_ERR(__wt_illegal_value(session, WT_METADATA_BACKUP));
WT_ERR(__wt_metadata_update(session, key->data, value->data));
}
/* Remove the hot backup file, it's only read (successfully) once. */
WT_ERR(__wt_remove(session, WT_METADATA_BACKUP));
err: if (fp != NULL)
WT_TRET(fclose(fp) == 0 ? 0 : __wt_errno());
if (path != NULL)
__wt_free(session, path);
__wt_scr_free(&key);
__wt_scr_free(&value);
return (ret);
}
/*
* __metadata_load_hot_backup --
* Load the contents of any hot backup file.
*/
static int
__metadata_load_hot_backup(WT_SESSION_IMPL *session)
{
FILE *fp;
WT_DECL_ITEM(key);
WT_DECL_ITEM(value);
WT_DECL_RET;
char *path;
fp = NULL;
path = NULL;
/* Look for a hot backup file: if we find it, load it. */
WT_RET(__wt_filename(session, WT_METADATA_BACKUP, &path));
fp = fopen(path, "r");
__wt_free(session, path);
if (fp == NULL)
return (0);
/* Read line pairs and load them into the metadata file. */
WT_ERR(__wt_scr_alloc(session, 512, &key));
WT_ERR(__wt_scr_alloc(session, 512, &value));
for (;;) {
WT_ERR(__wt_getline(session, key, fp));
if (key->size == 0)
break;
WT_ERR(__wt_getline(session, value, fp));
if (value->size == 0)
WT_ERR(__wt_illegal_value(session, WT_METADATA_BACKUP));
WT_ERR(__wt_metadata_update(session, key->data, value->data));
}
F_SET(S2C(session), WT_CONN_WAS_BACKUP);
err: if (fp != NULL)
WT_TRET(fclose(fp) == 0 ? 0 : __wt_errno());
__wt_scr_free(&key);
__wt_scr_free(&value);
return (ret);
}
/*
* __wt_btcur_update_check --
* Check whether an update would conflict.
*
* This can be used to replace WT_CURSOR::insert or WT_CURSOR::update, so
* they only check for conflicts without updating the tree. It is used to
* maintain snapshot isolation for transactions that span multiple chunks
* in an LSM tree.
*/
int
__wt_btcur_update_check(WT_CURSOR_BTREE *cbt)
{
WT_BTREE *btree;
WT_CURSOR *cursor;
WT_DECL_RET;
WT_SESSION_IMPL *session;
cursor = &cbt->iface;
btree = cbt->btree;
session = (WT_SESSION_IMPL *)cursor->session;
retry: WT_RET(__cursor_func_init(cbt, true));
switch (btree->type) {
case BTREE_ROW:
WT_ERR(__cursor_row_search(session, cbt, NULL, true));
/*
* Just check for conflicts.
*/
ret = __curfile_update_check(cbt);
break;
case BTREE_COL_FIX:
case BTREE_COL_VAR:
WT_ERR(__wt_illegal_value(session, NULL));
break;
}
err: if (ret == WT_RESTART) {
WT_STAT_CONN_INCR(session, cursor_restart);
WT_STAT_DATA_INCR(session, cursor_restart);
goto retry;
}
WT_TRET(__curfile_leave(cbt));
if (ret != 0)
WT_TRET(__cursor_reset(cbt));
return (ret);
}
/*
* __metadata_load_hot_backup --
* Load the contents of any hot backup file.
*/
static int
__metadata_load_hot_backup(WT_SESSION_IMPL *session)
{
WT_DECL_ITEM(key);
WT_DECL_ITEM(value);
WT_DECL_RET;
WT_FSTREAM *fs;
bool exist;
/* Look for a hot backup file: if we find it, load it. */
WT_RET(__wt_fs_exist(session, WT_METADATA_BACKUP, &exist));
if (!exist)
return (0);
WT_RET(__wt_fopen(session,
WT_METADATA_BACKUP, 0, WT_STREAM_READ, &fs));
/* Read line pairs and load them into the metadata file. */
WT_ERR(__wt_scr_alloc(session, 512, &key));
WT_ERR(__wt_scr_alloc(session, 512, &value));
for (;;) {
WT_ERR(__wt_getline(session, fs, key));
if (key->size == 0)
break;
WT_ERR(__wt_getline(session, fs, value));
if (value->size == 0)
WT_ERR(__wt_illegal_value(session, WT_METADATA_BACKUP));
WT_ERR(__wt_metadata_update(session, key->data, value->data));
}
F_SET(S2C(session), WT_CONN_WAS_BACKUP);
err: WT_TRET(__wt_fclose(session, &fs));
__wt_scr_free(session, &key);
__wt_scr_free(session, &value);
return (ret);
}
/*
* __wt_bt_read --
* Read a cookie referenced block into a buffer.
*/
int
__wt_bt_read(WT_SESSION_IMPL *session,
WT_ITEM *buf, const uint8_t *addr, size_t addr_size)
{
WT_BM *bm;
WT_BTREE *btree;
WT_DECL_ITEM(tmp);
WT_DECL_RET;
const WT_PAGE_HEADER *dsk;
size_t result_len;
btree = S2BT(session);
bm = btree->bm;
/*
* If anticipating a compressed block, read into a scratch buffer and
* decompress into the caller's buffer. Else, read directly into the
* caller's buffer.
*/
if (btree->compressor == NULL) {
WT_RET(bm->read(bm, session, buf, addr, addr_size));
dsk = buf->data;
} else {
WT_RET(__wt_scr_alloc(session, 0, &tmp));
WT_ERR(bm->read(bm, session, tmp, addr, addr_size));
dsk = tmp->data;
}
/*
* If the block is compressed, copy the skipped bytes of the original
* image into place, then decompress.
*/
if (F_ISSET(dsk, WT_PAGE_COMPRESSED)) {
if (btree->compressor == NULL ||
btree->compressor->decompress == NULL)
WT_ERR_MSG(session, WT_ERROR,
"read compressed block where no compression engine "
"configured");
/*
* We're allocating the exact number of bytes we're expecting
* from decompression.
*/
WT_ERR(__wt_buf_initsize(session, buf, dsk->mem_size));
/*
* Note the source length is NOT the number of compressed bytes,
* it's the length of the block we just read (minus the skipped
* bytes). We don't store the number of compressed bytes: some
* compression engines need that length stored externally, they
* don't have markers in the stream to signal the end of the
* compressed bytes. Those engines must store the compressed
* byte length somehow, see the snappy compression extension for
* an example.
*/
memcpy(buf->mem, tmp->data, WT_BLOCK_COMPRESS_SKIP);
ret = btree->compressor->decompress(
btree->compressor, &session->iface,
(uint8_t *)tmp->data + WT_BLOCK_COMPRESS_SKIP,
tmp->size - WT_BLOCK_COMPRESS_SKIP,
(uint8_t *)buf->mem + WT_BLOCK_COMPRESS_SKIP,
dsk->mem_size - WT_BLOCK_COMPRESS_SKIP, &result_len);
/*
* If checksums were turned off because we're depending on the
* decompression to fail on any corrupted data, we'll end up
* here after corruption happens. If we're salvaging the file,
* it's OK, otherwise it's really, really bad.
*/
if (ret != 0 ||
result_len != dsk->mem_size - WT_BLOCK_COMPRESS_SKIP)
WT_ERR(
F_ISSET(btree, WT_BTREE_VERIFY) ||
F_ISSET(session, WT_SESSION_SALVAGE_CORRUPT_OK) ?
WT_ERROR :
__wt_illegal_value(session, btree->dhandle->name));
} else
if (btree->compressor == NULL)
buf->size = dsk->mem_size;
else
/*
* We guessed wrong: there was a compressor, but this
* block was not compressed, and now the page is in the
* wrong buffer and the buffer may be of the wrong size.
* This should be rare, but happens with small blocks
* that aren't worth compressing.
*/
WT_ERR(__wt_buf_set(
session, buf, tmp->data, dsk->mem_size));
/* If the handle is a verify handle, verify the physical page. */
if (F_ISSET(btree, WT_BTREE_VERIFY)) {
if (tmp == NULL)
WT_ERR(__wt_scr_alloc(session, 0, &tmp));
WT_ERR(bm->addr_string(bm, session, tmp, addr, addr_size));
WT_ERR(__wt_verify_dsk(session, (const char *)tmp->data, buf));
}
WT_STAT_FAST_CONN_INCR(session, cache_read);
WT_STAT_FAST_DATA_INCR(session, cache_read);
if (F_ISSET(dsk, WT_PAGE_COMPRESSED))
WT_STAT_FAST_DATA_INCR(session, compress_read);
WT_STAT_FAST_CONN_INCRV(session, cache_bytes_read, dsk->mem_size);
WT_STAT_FAST_DATA_INCRV(session, cache_bytes_read, dsk->mem_size);
err: __wt_scr_free(session, &tmp);
return (ret);
}
/*
* __sync_file --
* Flush pages for a specific file.
*/
static int
__sync_file(WT_SESSION_IMPL *session, WT_CACHE_OP syncop)
{
WT_BTREE *btree;
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
WT_PAGE *page;
WT_PAGE_MODIFY *mod;
WT_REF *prev, *walk;
WT_TXN *txn;
uint64_t internal_bytes, internal_pages, leaf_bytes, leaf_pages;
uint64_t oldest_id, saved_pinned_id, time_start, time_stop;
uint32_t flags;
bool timer, tried_eviction;
conn = S2C(session);
btree = S2BT(session);
prev = walk = NULL;
txn = &session->txn;
tried_eviction = false;
time_start = time_stop = 0;
/* Only visit pages in cache and don't bump page read generations. */
flags = WT_READ_CACHE | WT_READ_NO_GEN;
/*
* Skip all deleted pages. For a page to be marked deleted, it must
* have been evicted from cache and marked clean. Checkpoint should
* never instantiate deleted pages: if a truncate is not visible to the
* checkpoint, the on-disk version is correct. If the truncate is
* visible, we skip over the child page when writing its parent. We
* check whether a truncate is visible in the checkpoint as part of
* reconciling internal pages (specifically in __rec_child_modify).
*/
LF_SET(WT_READ_DELETED_SKIP);
internal_bytes = leaf_bytes = 0;
internal_pages = leaf_pages = 0;
saved_pinned_id = WT_SESSION_TXN_STATE(session)->pinned_id;
timer = WT_VERBOSE_ISSET(session, WT_VERB_CHECKPOINT);
if (timer)
time_start = __wt_clock(session);
switch (syncop) {
case WT_SYNC_WRITE_LEAVES:
/*
* Write all immediately available, dirty in-cache leaf pages.
*
* Writing the leaf pages is done without acquiring a high-level
* lock, serialize so multiple threads don't walk the tree at
* the same time.
*/
if (!btree->modified)
return (0);
__wt_spin_lock(session, &btree->flush_lock);
if (!btree->modified) {
__wt_spin_unlock(session, &btree->flush_lock);
return (0);
}
/*
* Save the oldest transaction ID we need to keep around.
* Otherwise, in a busy system, we could be updating pages so
* fast that write leaves never catches up. We deliberately
* have no transaction running at this point that would keep
* the oldest ID from moving forwards as we walk the tree.
*/
oldest_id = __wt_txn_oldest_id(session);
LF_SET(WT_READ_NO_WAIT | WT_READ_SKIP_INTL);
for (;;) {
WT_ERR(__wt_tree_walk(session, &walk, flags));
if (walk == NULL)
break;
/*
* Write dirty pages if nobody beat us to it. Don't
* try to write hot pages (defined as pages that have
* been updated since the write phase leaves started):
* checkpoint will have to visit them anyway.
*/
page = walk->page;
if (__wt_page_is_modified(page) &&
WT_TXNID_LT(page->modify->update_txn, oldest_id)) {
if (txn->isolation == WT_ISO_READ_COMMITTED)
__wt_txn_get_snapshot(session);
leaf_bytes += page->memory_footprint;
++leaf_pages;
WT_ERR(__wt_reconcile(session,
walk, NULL, WT_REC_CHECKPOINT, NULL));
}
}
break;
case WT_SYNC_CHECKPOINT:
/*
* If we are flushing a file at read-committed isolation, which
* is of particular interest for flushing the metadata to make
* a schema-changing operation durable, get a transactional
* snapshot now.
*
* All changes committed up to this point should be included.
* We don't update the snapshot in between pages because the
* metadata shouldn't have many pages. Instead, read-committed
* isolation ensures that all metadata updates completed before
* the checkpoint are included.
*/
if (txn->isolation == WT_ISO_READ_COMMITTED)
__wt_txn_get_snapshot(session);
/*
* We cannot check the tree modified flag in the case of a
* checkpoint, the checkpoint code has already cleared it.
*
* Writing the leaf pages is done without acquiring a high-level
* lock, serialize so multiple threads don't walk the tree at
* the same time. We're holding the schema lock, but need the
* lower-level lock as well.
*/
__wt_spin_lock(session, &btree->flush_lock);
/*
* In the final checkpoint pass, child pages cannot be evicted
* from underneath internal pages nor can underlying blocks be
* freed until the checkpoint's block lists are stable. Also,
* we cannot split child pages into parents unless we know the
* final pass will write a consistent view of that namespace.
* Set the checkpointing flag to block such actions and wait for
* any problematic eviction or page splits to complete.
*/
WT_ASSERT(session, btree->syncing == WT_BTREE_SYNC_OFF &&
btree->sync_session == NULL);
btree->sync_session = session;
btree->syncing = WT_BTREE_SYNC_WAIT;
(void)__wt_gen_next_drain(session, WT_GEN_EVICT);
btree->syncing = WT_BTREE_SYNC_RUNNING;
/* Write all dirty in-cache pages. */
LF_SET(WT_READ_NO_EVICT);
/* Read pages with lookaside entries and evict them asap. */
LF_SET(WT_READ_LOOKASIDE | WT_READ_WONT_NEED);
for (;;) {
WT_ERR(__sync_dup_walk(session, walk, flags, &prev));
WT_ERR(__wt_tree_walk(session, &walk, flags));
if (walk == NULL)
break;
/*
* Skip clean pages, but need to make sure maximum
* transaction ID is always updated.
*/
if (!__wt_page_is_modified(walk->page)) {
if (((mod = walk->page->modify) != NULL) &&
mod->rec_max_txn > btree->rec_max_txn)
btree->rec_max_txn = mod->rec_max_txn;
if (mod != NULL &&
btree->rec_max_timestamp <
mod->rec_max_timestamp)
btree->rec_max_timestamp =
mod->rec_max_timestamp;
continue;
}
/*
* Take a local reference to the page modify structure
* now that we know the page is dirty. It needs to be
* done in this order otherwise the page modify
* structure could have been created between taking the
* reference and checking modified.
*/
page = walk->page;
/*
* Write dirty pages, if we can't skip them. If we skip
* a page, mark the tree dirty. The checkpoint marked it
* clean and we can't skip future checkpoints until this
* page is written.
*/
if (__sync_checkpoint_can_skip(session, page)) {
__wt_tree_modify_set(session);
continue;
}
if (WT_PAGE_IS_INTERNAL(page)) {
internal_bytes += page->memory_footprint;
++internal_pages;
} else {
leaf_bytes += page->memory_footprint;
++leaf_pages;
}
/*
* If the page was pulled into cache by our read, try
* to evict it now.
*
* For eviction to have a chance, we first need to move
* the walk point to the next page checkpoint will
* visit. We want to avoid this code being too special
* purpose, so try to reuse the ordinary eviction path.
*
* Regardless of whether eviction succeeds or fails,
* the walk continues from the previous location. We
* remember whether we tried eviction, and don't try
* again. Even if eviction fails (the page may stay in
* cache clean but with history that cannot be
* discarded), that is not wasted effort because
* checkpoint doesn't need to write the page again.
*/
if (!WT_PAGE_IS_INTERNAL(page) &&
page->read_gen == WT_READGEN_WONT_NEED &&
!tried_eviction) {
WT_ERR_BUSY_OK(
__wt_page_release_evict(session, walk));
walk = prev;
prev = NULL;
tried_eviction = true;
continue;
}
tried_eviction = false;
WT_ERR(__wt_reconcile(
session, walk, NULL, WT_REC_CHECKPOINT, NULL));
/*
* Update checkpoint IO tracking data if configured
* to log verbose progress messages.
*/
if (conn->ckpt_timer_start.tv_sec > 0) {
conn->ckpt_write_bytes +=
page->memory_footprint;
++conn->ckpt_write_pages;
/* Periodically log checkpoint progress. */
if (conn->ckpt_write_pages % 5000 == 0)
__wt_checkpoint_progress(
session, false);
}
}
break;
case WT_SYNC_CLOSE:
case WT_SYNC_DISCARD:
WT_ERR(__wt_illegal_value(session, syncop));
break;
}
if (timer) {
time_stop = __wt_clock(session);
__wt_verbose(session, WT_VERB_CHECKPOINT,
"__sync_file WT_SYNC_%s wrote: %" PRIu64
" leaf pages (%" PRIu64 "B), %" PRIu64
" internal pages (%" PRIu64 "B), and took %" PRIu64 "ms",
syncop == WT_SYNC_WRITE_LEAVES ?
"WRITE_LEAVES" : "CHECKPOINT",
leaf_pages, leaf_bytes, internal_pages, internal_bytes,
WT_CLOCKDIFF_MS(time_stop, time_start));
}
err: /* On error, clear any left-over tree walk. */
WT_TRET(__wt_page_release(session, walk, flags));
WT_TRET(__wt_page_release(session, prev, flags));
/*
* If we got a snapshot in order to write pages, and there was no
* snapshot active when we started, release it.
*/
if (txn->isolation == WT_ISO_READ_COMMITTED &&
saved_pinned_id == WT_TXN_NONE)
__wt_txn_release_snapshot(session);
/* Clear the checkpoint flag. */
btree->syncing = WT_BTREE_SYNC_OFF;
btree->sync_session = NULL;
__wt_spin_unlock(session, &btree->flush_lock);
/*
* Leaves are written before a checkpoint (or as part of a file close,
* before checkpointing the file). Start a flush to stable storage,
* but don't wait for it.
*/
if (ret == 0 &&
syncop == WT_SYNC_WRITE_LEAVES && F_ISSET(conn, WT_CONN_CKPT_SYNC))
WT_RET(btree->bm->sync(btree->bm, session, false));
return (ret);
}
/*
* __wt_merge_tree --
* Attempt to collapse a stack of split-merge pages in memory into a
* shallow tree. If enough keys are found, create a real internal node
* that can be evicted (and, if necessary, split further).
*
* This code is designed to deal with workloads that otherwise create
* arbitrarily deep (and slow) trees in memory.
*/
int
__wt_merge_tree(WT_SESSION_IMPL *session, WT_PAGE *top)
{
WT_DECL_RET;
WT_PAGE *lchild, *newtop, *rchild;
WT_REF *newref;
WT_VISIT_STATE visit_state;
uint32_t refcnt, split;
int promote;
u_int levels;
uint8_t page_type;
WT_CLEAR(visit_state);
visit_state.session = session;
lchild = newtop = rchild = NULL;
page_type = top->type;
WT_ASSERT(session, __wt_btree_mergeable(top));
WT_ASSERT(session, top->ref->state == WT_REF_LOCKED);
/*
* Walk the subtree, count the references at the bottom level and
* calculate the maximum depth.
*/
WT_RET(__merge_walk(session, top, 1, __merge_count, &visit_state));
/* If there aren't enough useful levels, give up. */
if (visit_state.maxdepth < WT_MERGE_STACK_MIN)
return (EBUSY);
/*
* Don't allow split merges to generate arbitrarily large pages.
* Ideally we would choose a size based on the internal_page_max
* setting for the btree, but we don't have the correct btree handle
* available.
*/
if (visit_state.refcnt > WT_MERGE_MAX_REFS)
return (EBUSY);
/*
* Now we either collapse the internal pages into one split-merge page,
* or if there are "enough" keys, we split into two equal internal
* pages, each of which can be evicted independently.
*
* We set a flag (WT_PM_REC_SPLIT_MERGE) on the created page if it
* isn't big enough to justify the cost of evicting it. If splits
* continue, it will be merged again until it gets over this limit.
*/
promote = 0;
refcnt = (uint32_t)visit_state.refcnt;
if (refcnt >= WT_MERGE_FULL_PAGE && visit_state.seen_live) {
/*
* In the normal case where there are live children spread
* through the subtree, create two child pages.
*
* Handle the case where the only live child is first / last
* specially: put the live child into the top-level page.
*
* Set SPLIT_MERGE on the internal pages if there are any live
* children: they can't be evicted, so there is no point
* permanently deepening the tree.
*/
if (visit_state.first_live == visit_state.last_live &&
(visit_state.first_live == 0 ||
visit_state.first_live == refcnt - 1))
split = (visit_state.first_live == 0) ? 1 : refcnt - 1;
else
split = (refcnt + 1) / 2;
/* Only promote if we can create a real page. */
if (split == 1 || split == refcnt - 1)
promote = 1;
else if (split >= WT_MERGE_FULL_PAGE &&
visit_state.first_live >= split)
promote = 1;
else if (refcnt - split >= WT_MERGE_FULL_PAGE &&
visit_state.last_live < split)
promote = 1;
}
if (promote) {
/* Create a new top-level split-merge page with two entries. */
WT_ERR(__merge_new_page(session, page_type, 2, 1, &newtop));
visit_state.split = split;
/* Left split. */
if (split == 1)
visit_state.first = newtop;
else {
WT_ERR(__merge_new_page(session, page_type, split,
visit_state.first_live < split, &lchild));
visit_state.first = lchild;
}
/* Right split. */
if (split == refcnt - 1) {
visit_state.second = newtop;
visit_state.second_ref = &newtop->u.intl.t[1];
} else {
WT_ERR(__merge_new_page(session, page_type,
refcnt - split, visit_state.last_live >= split,
&rchild));
visit_state.second = rchild;
visit_state.second_ref =
&visit_state.second->u.intl.t[0];
}
} else {
/*
* Create a new split-merge page for small merges, or if the
* page above is a split merge page. When we do a big enough
* merge, we create a real page at the top and don't consider
* it as a merge candidate again. Over time with an insert
* workload the tree will grow deeper, but that's inevitable,
* and this keeps individual merges small.
*/
WT_ERR(__merge_new_page(session, page_type, refcnt,
refcnt < WT_MERGE_FULL_PAGE ||
__wt_btree_mergeable(top->parent),
&newtop));
visit_state.first = newtop;
}
/*
* Copy the references into the new tree, but don't update anything in
* the locked tree in case there is an error and we need to back out.
* We do this in a separate pass so that we can figure out the key for
* the split point: that allocates memory and so it could still fail.
*/
visit_state.page = visit_state.first;
visit_state.ref = visit_state.page->u.intl.t;
visit_state.refcnt = 0;
WT_ERR(__merge_walk(session, top, 0, __merge_copy_ref, &visit_state));
if (promote) {
/* Promote keys into the top-level page. */
if (lchild != NULL) {
newref = &newtop->u.intl.t[0];
WT_LINK_PAGE(newtop, newref, lchild);
newref->state = WT_REF_MEM;
WT_ERR(__merge_promote_key(session, newref));
}
if (rchild != NULL) {
newref = &newtop->u.intl.t[1];
WT_LINK_PAGE(newtop, newref, rchild);
newref->state = WT_REF_MEM;
WT_ERR(__merge_promote_key(session, newref));
}
}
/*
* We have copied everything into place and allocated all of the memory
* we need. Now link all pages into the new tree and unlock them.
*
* The only way this could fail is if a reference state has been
* changed by another thread since they were locked. Panic in that
* case: that should never happen.
*/
visit_state.page = visit_state.first;
visit_state.ref = visit_state.page->u.intl.t;
visit_state.refcnt = 0;
ret = __merge_walk(session, top, 0, __merge_switch_page, &visit_state);
if (ret != 0)
WT_ERR(__wt_illegal_value(session, "__wt_merge_tree"));
newtop->u.intl.recno = top->u.intl.recno;
newtop->parent = top->parent;
newtop->ref = top->ref;
#ifdef HAVE_DIAGNOSTIC
/*
* Before swapping in the new tree, walk the pages we are discarding,
* check that everything looks right.
*/
__merge_check_discard(session, top);
#endif
/*
* Set up the new top-level page as a split so that it will be swapped
* into place by our caller.
*/
top->modify->flags = WT_PM_REC_SPLIT;
top->modify->u.split = newtop;
WT_VERBOSE_ERR(session, evict,
"Successfully %s %" PRIu32
" split-merge pages containing %" PRIu32 " keys\n",
promote ? "promoted" : "merged", visit_state.maxdepth, refcnt);
/* Evict new child pages as soon as possible. */
if (lchild != NULL && !F_ISSET(lchild->modify, WT_PM_REC_SPLIT_MERGE))
lchild->read_gen = WT_READ_GEN_OLDEST;
if (rchild != NULL && !F_ISSET(rchild->modify, WT_PM_REC_SPLIT_MERGE))
rchild->read_gen = WT_READ_GEN_OLDEST;
/* Update statistics. */
WT_CSTAT_INCR(session, cache_eviction_merge);
WT_DSTAT_INCR(session, cache_eviction_merge);
/* How many levels did we remove? */
levels = visit_state.maxdepth - (promote ? 2 : 1);
WT_CSTAT_INCRV(session, cache_eviction_merge_levels, levels);
WT_DSTAT_INCRV(session, cache_eviction_merge_levels, levels);
return (0);
err: WT_VERBOSE_TRET(session, evict,
"Failed to merge %" PRIu32
" split-merge pages containing %" PRIu32 " keys\n",
visit_state.maxdepth, refcnt);
WT_CSTAT_INCR(session, cache_eviction_merge_fail);
WT_DSTAT_INCR(session, cache_eviction_merge_fail);
if (newtop != NULL)
__wt_page_out(session, &newtop);
if (lchild != NULL)
__wt_page_out(session, &lchild);
if (rchild != NULL)
__wt_page_out(session, &rchild);
return (ret);
}
/*
* __wt_bt_read --
* Read a cookie referenced block into a buffer.
*/
int
__wt_bt_read(WT_SESSION_IMPL *session,
WT_ITEM *buf, const uint8_t *addr, size_t addr_size)
{
WT_BM *bm;
WT_BTREE *btree;
WT_DECL_ITEM(etmp);
WT_DECL_ITEM(tmp);
WT_DECL_RET;
WT_ENCRYPTOR *encryptor;
WT_ITEM *ip;
const WT_PAGE_HEADER *dsk;
const char *fail_msg;
size_t result_len;
btree = S2BT(session);
bm = btree->bm;
fail_msg = NULL; /* -Wuninitialized */
/*
* If anticipating a compressed or encrypted block, read into a scratch
* buffer and decompress into the caller's buffer. Else, read directly
* into the caller's buffer.
*/
if (btree->compressor == NULL && btree->kencryptor == NULL) {
WT_RET(bm->read(bm, session, buf, addr, addr_size));
dsk = buf->data;
ip = NULL;
} else {
WT_RET(__wt_scr_alloc(session, 0, &tmp));
WT_ERR(bm->read(bm, session, tmp, addr, addr_size));
dsk = tmp->data;
ip = tmp;
}
/*
* If the block is encrypted, copy the skipped bytes of the original
* image into place, then decrypt.
*/
if (F_ISSET(dsk, WT_PAGE_ENCRYPTED)) {
if (btree->kencryptor == NULL ||
(encryptor = btree->kencryptor->encryptor) == NULL ||
encryptor->decrypt == NULL) {
fail_msg =
"encrypted block in file for which no encryption "
"configured";
goto corrupt;
}
WT_ERR(__wt_scr_alloc(session, 0, &etmp));
if ((ret = __wt_decrypt(session,
encryptor, WT_BLOCK_ENCRYPT_SKIP, ip, etmp)) != 0) {
fail_msg = "block decryption failed";
goto corrupt;
}
ip = etmp;
dsk = ip->data;
} else if (btree->kencryptor != NULL) {
fail_msg =
"unencrypted block in file for which encryption configured";
goto corrupt;
}
if (F_ISSET(dsk, WT_PAGE_COMPRESSED)) {
if (btree->compressor == NULL ||
btree->compressor->decompress == NULL) {
fail_msg =
"compressed block in file for which no compression "
"configured";
goto corrupt;
}
/*
* Size the buffer based on the in-memory bytes we're expecting
* from decompression.
*/
WT_ERR(__wt_buf_initsize(session, buf, dsk->mem_size));
/*
* Note the source length is NOT the number of compressed bytes,
* it's the length of the block we just read (minus the skipped
* bytes). We don't store the number of compressed bytes: some
* compression engines need that length stored externally, they
* don't have markers in the stream to signal the end of the
* compressed bytes. Those engines must store the compressed
* byte length somehow, see the snappy compression extension for
* an example.
*/
memcpy(buf->mem, ip->data, WT_BLOCK_COMPRESS_SKIP);
ret = btree->compressor->decompress(
btree->compressor, &session->iface,
(uint8_t *)ip->data + WT_BLOCK_COMPRESS_SKIP,
tmp->size - WT_BLOCK_COMPRESS_SKIP,
(uint8_t *)buf->mem + WT_BLOCK_COMPRESS_SKIP,
dsk->mem_size - WT_BLOCK_COMPRESS_SKIP, &result_len);
/*
* If checksums were turned off because we're depending on the
* decompression to fail on any corrupted data, we'll end up
* here after corruption happens. If we're salvaging the file,
* it's OK, otherwise it's really, really bad.
*/
if (ret != 0 ||
result_len != dsk->mem_size - WT_BLOCK_COMPRESS_SKIP) {
fail_msg = "block decryption failed";
goto corrupt;
}
} else
/*
* If we uncompressed above, the page is in the correct buffer.
* If we get here the data may be in the wrong buffer and the
* buffer may be the wrong size. If needed, get the page
* into the destination buffer.
*/
if (ip != NULL)
WT_ERR(__wt_buf_set(
session, buf, ip->data, dsk->mem_size));
/* If the handle is a verify handle, verify the physical page. */
if (F_ISSET(btree, WT_BTREE_VERIFY)) {
if (tmp == NULL)
WT_ERR(__wt_scr_alloc(session, 0, &tmp));
WT_ERR(bm->addr_string(bm, session, tmp, addr, addr_size));
WT_ERR(__wt_verify_dsk(session, tmp->data, buf));
}
WT_STAT_FAST_CONN_INCR(session, cache_read);
WT_STAT_FAST_DATA_INCR(session, cache_read);
if (F_ISSET(dsk, WT_PAGE_COMPRESSED))
WT_STAT_FAST_DATA_INCR(session, compress_read);
WT_STAT_FAST_CONN_INCRV(session, cache_bytes_read, dsk->mem_size);
WT_STAT_FAST_DATA_INCRV(session, cache_bytes_read, dsk->mem_size);
if (0) {
corrupt: if (ret == 0)
ret = WT_ERROR;
if (!F_ISSET(btree, WT_BTREE_VERIFY) &&
!F_ISSET(session, WT_SESSION_QUIET_CORRUPT_FILE)) {
__wt_err(session, ret, "%s", fail_msg);
ret = __wt_illegal_value(session, btree->dhandle->name);
}
}
err: __wt_scr_free(session, &tmp);
__wt_scr_free(session, &etmp);
return (ret);
}
/*
* __wt_block_read_off --
* Read an addr/size pair referenced block into a buffer.
*/
int
__wt_block_read_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
WT_ITEM *buf, wt_off_t offset, uint32_t size, uint32_t cksum)
{
WT_BLOCK_HEADER *blk, swap;
size_t bufsize;
uint32_t page_cksum;
__wt_verbose(session, WT_VERB_READ,
"off %" PRIuMAX ", size %" PRIu32 ", cksum %" PRIu32,
(uintmax_t)offset, size, cksum);
WT_STAT_FAST_CONN_INCR(session, block_read);
WT_STAT_FAST_CONN_INCRV(session, block_byte_read, size);
/*
* Grow the buffer as necessary and read the block. Buffers should be
* aligned for reading, but there are lots of buffers (for example, file
* cursors have two buffers each, key and value), and it's difficult to
* be sure we've found all of them. If the buffer isn't aligned, it's
* an easy fix: set the flag and guarantee we reallocate it. (Most of
* the time on reads, the buffer memory has not yet been allocated, so
* we're not adding any additional processing time.)
*/
if (F_ISSET(buf, WT_ITEM_ALIGNED))
bufsize = size;
else {
F_SET(buf, WT_ITEM_ALIGNED);
bufsize = WT_MAX(size, buf->memsize + 10);
}
WT_RET(__wt_buf_init(session, buf, bufsize));
WT_RET(__wt_read(session, block->fh, offset, size, buf->mem));
buf->size = size;
/*
* We incrementally read through the structure before doing a checksum,
* do little- to big-endian handling early on, and then select from the
* original or swapped structure as needed.
*/
blk = WT_BLOCK_HEADER_REF(buf->mem);
__wt_block_header_byteswap_copy(blk, &swap);
if (swap.cksum == cksum) {
blk->cksum = 0;
page_cksum = __wt_cksum(buf->mem,
F_ISSET(&swap, WT_BLOCK_DATA_CKSUM) ?
size : WT_BLOCK_COMPRESS_SKIP);
if (page_cksum == cksum) {
/*
* Swap the page-header as needed; this doesn't belong
* here, but it's the best place to catch all callers.
*/
__wt_page_header_byteswap(buf->mem);
return (0);
}
if (!F_ISSET(session, WT_SESSION_QUIET_CORRUPT_FILE))
__wt_errx(session,
"read checksum error for %" PRIu32 "B block at "
"offset %" PRIuMAX ": calculated block checksum "
"of %" PRIu32 " doesn't match expected checksum "
"of %" PRIu32,
size, (uintmax_t)offset, page_cksum, cksum);
} else
if (!F_ISSET(session, WT_SESSION_QUIET_CORRUPT_FILE))
__wt_errx(session,
"read checksum error for %" PRIu32 "B block at "
"offset %" PRIuMAX ": block header checksum "
"of %" PRIu32 " doesn't match expected checksum "
"of %" PRIu32,
size, (uintmax_t)offset, swap.cksum, cksum);
/* Panic if a checksum fails during an ordinary read. */
return (block->verify ||
F_ISSET(session, WT_SESSION_QUIET_CORRUPT_FILE) ?
WT_ERROR : __wt_illegal_value(session, block->name));
}
/*
* __wt_lsm_meta_read --
* Read the metadata for an LSM tree.
*/
int
__wt_lsm_meta_read(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
{
WT_CONFIG cparser, lparser;
WT_CONFIG_ITEM ck, cv, fileconf, lk, lv, metadata;
WT_DECL_RET;
WT_LSM_CHUNK *chunk;
char *lsmconfig;
u_int nchunks;
chunk = NULL; /* -Wconditional-uninitialized */
WT_RET(__wt_metadata_search(session, lsm_tree->name, &lsmconfig));
WT_ERR(__wt_config_init(session, &cparser, lsmconfig));
while ((ret = __wt_config_next(&cparser, &ck, &cv)) == 0) {
if (WT_STRING_MATCH("key_format", ck.str, ck.len)) {
__wt_free(session, lsm_tree->key_format);
WT_ERR(__wt_strndup(session,
cv.str, cv.len, &lsm_tree->key_format));
} else if (WT_STRING_MATCH("value_format", ck.str, ck.len)) {
__wt_free(session, lsm_tree->value_format);
WT_ERR(__wt_strndup(session,
cv.str, cv.len, &lsm_tree->value_format));
} else if (WT_STRING_MATCH("collator", ck.str, ck.len)) {
if (cv.len == 0 ||
WT_STRING_CASE_MATCH("none", cv.str, cv.len))
continue;
/*
* Extract the application-supplied metadata (if any)
* from the file configuration.
*/
WT_ERR(__wt_config_getones(
session, lsmconfig, "file_config", &fileconf));
WT_CLEAR(metadata);
WT_ERR_NOTFOUND_OK(__wt_config_subgets(
session, &fileconf, "app_metadata", &metadata));
WT_ERR(__wt_collator_config(session, lsm_tree->name,
&cv, &metadata,
&lsm_tree->collator, &lsm_tree->collator_owned));
WT_ERR(__wt_strndup(session,
cv.str, cv.len, &lsm_tree->collator_name));
} else if (WT_STRING_MATCH("bloom_config", ck.str, ck.len)) {
__wt_free(session, lsm_tree->bloom_config);
/* Don't include the brackets. */
WT_ERR(__wt_strndup(session,
cv.str + 1, cv.len - 2, &lsm_tree->bloom_config));
} else if (WT_STRING_MATCH("file_config", ck.str, ck.len)) {
__wt_free(session, lsm_tree->file_config);
/* Don't include the brackets. */
WT_ERR(__wt_strndup(session,
cv.str + 1, cv.len - 2, &lsm_tree->file_config));
} else if (WT_STRING_MATCH("auto_throttle", ck.str, ck.len)) {
if (cv.val)
F_SET(lsm_tree, WT_LSM_TREE_THROTTLE);
else
F_CLR(lsm_tree, WT_LSM_TREE_THROTTLE);
} else if (WT_STRING_MATCH("bloom", ck.str, ck.len))
lsm_tree->bloom = (uint32_t)cv.val;
else if (WT_STRING_MATCH("bloom_bit_count", ck.str, ck.len))
lsm_tree->bloom_bit_count = (uint32_t)cv.val;
else if (WT_STRING_MATCH("bloom_hash_count", ck.str, ck.len))
lsm_tree->bloom_hash_count = (uint32_t)cv.val;
else if (WT_STRING_MATCH("chunk_max", ck.str, ck.len))
lsm_tree->chunk_max = (uint64_t)cv.val;
else if (WT_STRING_MATCH("chunk_size", ck.str, ck.len))
lsm_tree->chunk_size = (uint64_t)cv.val;
else if (WT_STRING_MATCH("merge_max", ck.str, ck.len))
lsm_tree->merge_max = (uint32_t)cv.val;
else if (WT_STRING_MATCH("merge_min", ck.str, ck.len))
lsm_tree->merge_min = (uint32_t)cv.val;
else if (WT_STRING_MATCH("last", ck.str, ck.len))
lsm_tree->last = (u_int)cv.val;
else if (WT_STRING_MATCH("chunks", ck.str, ck.len)) {
WT_ERR(__wt_config_subinit(session, &lparser, &cv));
for (nchunks = 0; (ret =
__wt_config_next(&lparser, &lk, &lv)) == 0; ) {
if (WT_STRING_MATCH("id", lk.str, lk.len)) {
WT_ERR(__wt_realloc_def(session,
&lsm_tree->chunk_alloc,
nchunks + 1, &lsm_tree->chunk));
WT_ERR(
__wt_calloc_one(session, &chunk));
lsm_tree->chunk[nchunks++] = chunk;
chunk->id = (uint32_t)lv.val;
WT_ERR(__wt_lsm_tree_chunk_name(session,
lsm_tree, chunk->id, &chunk->uri));
F_SET(chunk,
WT_LSM_CHUNK_ONDISK |
WT_LSM_CHUNK_STABLE);
} else if (WT_STRING_MATCH(
"bloom", lk.str, lk.len)) {
WT_ERR(__wt_lsm_tree_bloom_name(
session, lsm_tree,
chunk->id, &chunk->bloom_uri));
F_SET(chunk, WT_LSM_CHUNK_BLOOM);
continue;
} else if (WT_STRING_MATCH(
"chunk_size", lk.str, lk.len)) {
chunk->size = (uint64_t)lv.val;
continue;
} else if (WT_STRING_MATCH(
"count", lk.str, lk.len)) {
chunk->count = (uint64_t)lv.val;
continue;
} else if (WT_STRING_MATCH(
"generation", lk.str, lk.len)) {
chunk->generation = (uint32_t)lv.val;
continue;
}
}
WT_ERR_NOTFOUND_OK(ret);
lsm_tree->nchunks = nchunks;
} else if (WT_STRING_MATCH("old_chunks", ck.str, ck.len)) {
WT_ERR(__wt_config_subinit(session, &lparser, &cv));
for (nchunks = 0; (ret =
__wt_config_next(&lparser, &lk, &lv)) == 0; ) {
if (WT_STRING_MATCH("bloom", lk.str, lk.len)) {
WT_ERR(__wt_strndup(session,
lv.str, lv.len, &chunk->bloom_uri));
F_SET(chunk, WT_LSM_CHUNK_BLOOM);
continue;
}
WT_ERR(__wt_realloc_def(session,
&lsm_tree->old_alloc, nchunks + 1,
&lsm_tree->old_chunks));
WT_ERR(__wt_calloc_one(session, &chunk));
lsm_tree->old_chunks[nchunks++] = chunk;
WT_ERR(__wt_strndup(session,
lk.str, lk.len, &chunk->uri));
F_SET(chunk, WT_LSM_CHUNK_ONDISK);
}
WT_ERR_NOTFOUND_OK(ret);
lsm_tree->nold_chunks = nchunks;
/* Values included for backward compatibility */
} else if (WT_STRING_MATCH("merge_threads", ck.str, ck.len)) {
} else
WT_ERR(__wt_illegal_value(session, "LSM metadata"));
}
WT_ERR_NOTFOUND_OK(ret);
/*
* If the default merge_min was not overridden, calculate it now. We
* do this here so that trees created before merge_min was added get a
* sane value.
*/
if (lsm_tree->merge_min < 2)
lsm_tree->merge_min = WT_MAX(2, lsm_tree->merge_max / 2);
err: __wt_free(session, lsmconfig);
return (ret);
}
/*
* __wt_block_read_off --
* Read an addr/size pair referenced block into a buffer.
*/
int
__wt_block_read_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
WT_ITEM *buf, off_t offset, uint32_t size, uint32_t cksum)
{
WT_BLOCK_HEADER *blk;
WT_DECL_ITEM(tmp);
WT_DECL_RET;
WT_PAGE_HEADER *dsk;
size_t result_len;
uint32_t page_cksum;
WT_VERBOSE_RET(session, read,
"off %" PRIuMAX ", size %" PRIu32 ", cksum %" PRIu32,
(uintmax_t)offset, size, cksum);
#ifdef HAVE_DIAGNOSTIC
/*
* In diagnostic mode, verify the block we're about to read isn't on
* either the available or discard lists.
*
* Don't check during salvage, it's possible we're reading an already
* freed overflow page.
*/
if (!F_ISSET(session, WT_SESSION_SALVAGE_QUIET_ERR))
WT_RET(
__wt_block_misplaced(session, block, "read", offset, size));
#endif
/*
* If we're compressing the file blocks, place the initial read into a
* scratch buffer, we're going to have to re-allocate more memory for
* decompression. Else check the caller's buffer size and grow it as
* necessary, there will only be one buffer.
*/
if (block->compressor == NULL) {
F_SET(buf, WT_ITEM_ALIGNED);
WT_RET(__wt_buf_init(session, buf, size));
buf->size = size;
dsk = buf->mem;
} else {
WT_RET(__wt_scr_alloc(session, size, &tmp));
tmp->size = size;
dsk = tmp->mem;
}
/* Read. */
WT_ERR(__wt_read(session, block->fh, offset, size, dsk));
blk = WT_BLOCK_HEADER_REF(dsk);
/* Validate the checksum. */
if (block->checksum &&
cksum != WT_BLOCK_CHECKSUM_NOT_SET &&
blk->cksum != WT_BLOCK_CHECKSUM_NOT_SET) {
blk->cksum = 0;
page_cksum = __wt_cksum(dsk, size);
if (page_cksum == WT_BLOCK_CHECKSUM_NOT_SET)
++page_cksum;
if (cksum != page_cksum) {
if (!F_ISSET(session, WT_SESSION_SALVAGE_QUIET_ERR))
__wt_errx(session,
"read checksum error [%"
PRIu32 "B @ %" PRIuMAX ", %"
PRIu32 " != %" PRIu32 "]",
size, (uintmax_t)offset, cksum, page_cksum);
WT_ERR(WT_ERROR);
}
}
/*
* If the in-memory block size is larger than the on-disk block size,
* the block is compressed. Size the user's buffer, copy the skipped
* bytes of the original image into place, then decompress.
*
* If the in-memory block size is less than or equal to the on-disk
* block size, the block is not compressed.
*/
if (blk->disk_size < dsk->size) {
if (block->compressor == NULL)
WT_ERR(__wt_illegal_value(session, block->name));
WT_ERR(__wt_buf_init(session, buf, dsk->size));
buf->size = dsk->size;
/*
* Note the source length is NOT the number of compressed bytes,
* it's the length of the block we just read (minus the skipped
* bytes). We don't store the number of compressed bytes: some
* compression engines need that length stored externally, they
* don't have markers in the stream to signal the end of the
* compressed bytes. Those engines must store the compressed
* byte length somehow, see the snappy compression extension for
* an example.
*/
memcpy(buf->mem, tmp->mem, WT_BLOCK_COMPRESS_SKIP);
WT_ERR(block->compressor->decompress(
block->compressor, &session->iface,
(uint8_t *)tmp->mem + WT_BLOCK_COMPRESS_SKIP,
tmp->size - WT_BLOCK_COMPRESS_SKIP,
(uint8_t *)buf->mem + WT_BLOCK_COMPRESS_SKIP,
dsk->size - WT_BLOCK_COMPRESS_SKIP,
&result_len));
if (result_len != dsk->size - WT_BLOCK_COMPRESS_SKIP)
WT_ERR(__wt_illegal_value(session, block->name));
} else
if (block->compressor == NULL)
buf->size = dsk->size;
else
/*
* We guessed wrong: there was a compressor, but this
* block was not compressed, and now the page is in the
* wrong buffer and the buffer may be of the wrong size.
* This should be rare, why configure a compressor that
* doesn't work? Allocate a buffer of the right size
* (we used a scratch buffer which might be large), and
* copy the data into place.
*/
WT_ERR(
__wt_buf_set(session, buf, tmp->data, dsk->size));
WT_BSTAT_INCR(session, page_read);
WT_CSTAT_INCR(session, block_read);
err: __wt_scr_free(&tmp);
return (ret);
}
