/*
* __wt_ovfl_txnc_add --
* Add a new entry to the page's list of transaction-cached overflow
* records.
*/
int
__wt_ovfl_txnc_add(WT_SESSION_IMPL *session, WT_PAGE *page,
const uint8_t *addr, size_t addr_size,
const void *value, size_t value_size)
{
WT_OVFL_TXNC **head, **stack[WT_SKIP_MAXDEPTH], *txnc;
size_t size;
u_int i, skipdepth;
uint8_t *p;
if (page->modify->ovfl_track == NULL)
WT_RET(__ovfl_track_init(session, page));
head = page->modify->ovfl_track->ovfl_txnc;
/* Choose a skiplist depth for this insert. */
skipdepth = __wt_skip_choose_depth(session);
/*
* Allocate the WT_OVFL_TXNC structure, next pointers for the skip
* list, room for the address and value, then copy everything into
* place.
*
* To minimize the WT_OVFL_TXNC structure size, the address offset
* and size are single bytes: that's safe because the address follows
* the structure (which can't be more than about 100B), and address
* cookies are limited to 255B.
*/
size = sizeof(WT_OVFL_TXNC) +
skipdepth * sizeof(WT_OVFL_TXNC *) + addr_size + value_size;
WT_RET(__wt_calloc(session, 1, size, &txnc));
p = (uint8_t *)txnc +
sizeof(WT_OVFL_TXNC) + skipdepth * sizeof(WT_OVFL_TXNC *);
txnc->addr_offset = (uint8_t)WT_PTRDIFF(p, txnc);
txnc->addr_size = (uint8_t)addr_size;
memcpy(p, addr, addr_size);
p += addr_size;
txnc->value_offset = WT_PTRDIFF32(p, txnc);
txnc->value_size = WT_STORE_SIZE(value_size);
memcpy(p, value, value_size);
txnc->current = __wt_txn_new_id(session);
__wt_cache_page_inmem_incr(
session, page, WT_OVFL_SIZE(txnc, WT_OVFL_TXNC));
/* Insert the new entry into the skiplist. */
__ovfl_txnc_skip_search_stack(head, stack, addr, addr_size);
for (i = 0; i < skipdepth; ++i) {
txnc->next[i] = *stack[i];
*stack[i] = txnc;
}
if (WT_VERBOSE_ISSET(session, WT_VERB_OVERFLOW))
WT_RET(__ovfl_txnc_verbose(session, page, txnc, "add"));
return (0);
}
/*
* __wt_lsm_tree_switch --
* Switch to a new in-memory tree.
*/
int
__wt_lsm_tree_switch(WT_SESSION_IMPL *session, WT_LSM_TREE *lsm_tree)
{
WT_DECL_RET;
WT_LSM_CHUNK *chunk;
uint32_t nchunks, new_id;
int first_switch;
WT_RET(__wt_lsm_tree_writelock(session, lsm_tree));
nchunks = lsm_tree->nchunks;
first_switch = nchunks == 0 ? 1 : 0;
/*
* Check if a switch is still needed: we may have raced while waiting
* for a lock.
*/
chunk = NULL;
if (!first_switch &&
(chunk = lsm_tree->chunk[nchunks - 1]) != NULL &&
!F_ISSET(chunk, WT_LSM_CHUNK_ONDISK) &&
!F_ISSET(lsm_tree, WT_LSM_TREE_NEED_SWITCH))
goto err;
/* Set the switch transaction in the previous chunk, if necessary. */
if (chunk != NULL && chunk->switch_txn == WT_TXN_NONE)
chunk->switch_txn = __wt_txn_new_id(session);
/* Update the throttle time. */
__wt_lsm_tree_throttle(session, lsm_tree, 0);
new_id = WT_ATOMIC_ADD4(lsm_tree->last, 1);
WT_ERR(__wt_realloc_def(session, &lsm_tree->chunk_alloc,
nchunks + 1, &lsm_tree->chunk));
WT_ERR(__wt_verbose(session, WT_VERB_LSM,
"Tree %s switch to: %" PRIu32 ", checkpoint throttle %ld, "
"merge throttle %ld", lsm_tree->name,
new_id, lsm_tree->ckpt_throttle, lsm_tree->merge_throttle));
WT_ERR(__wt_calloc_def(session, 1, &chunk));
chunk->id = new_id;
chunk->switch_txn = WT_TXN_NONE;
lsm_tree->chunk[lsm_tree->nchunks++] = chunk;
WT_ERR(__wt_lsm_tree_setup_chunk(session, lsm_tree, chunk));
WT_ERR(__wt_lsm_meta_write(session, lsm_tree));
F_CLR(lsm_tree, WT_LSM_TREE_NEED_SWITCH);
++lsm_tree->dsk_gen;
lsm_tree->modified = 1;
err: WT_TRET(__wt_lsm_tree_writeunlock(session, lsm_tree));
/*
* Errors that happen during a tree switch leave the tree in a state
* where we can't make progress. Error out of WiredTiger.
*/
if (ret != 0)
WT_PANIC_RET(session, ret, "Failed doing LSM switch");
else if (!first_switch)
WT_RET(__wt_lsm_manager_push_entry(
session, WT_LSM_WORK_FLUSH, 0, lsm_tree));
return (ret);
}
/*
* __wt_lsm_compact --
* Compact an LSM tree called via __wt_schema_worker.
*/
int
__wt_lsm_compact(WT_SESSION_IMPL *session, const char *name, int *skip)
{
WT_DECL_RET;
WT_LSM_CHUNK *chunk;
WT_LSM_TREE *lsm_tree;
time_t begin, end;
uint64_t progress;
int i, compacting, flushing, locked, ref;
compacting = flushing = locked = ref = 0;
chunk = NULL;
/*
* This function is applied to all matching sources: ignore anything
* that is not an LSM tree.
*/
if (!WT_PREFIX_MATCH(name, "lsm:"))
return (0);
/* Tell __wt_schema_worker not to look inside the LSM tree. */
*skip = 1;
WT_RET(__wt_lsm_tree_get(session, name, 0, &lsm_tree));
if (!F_ISSET(S2C(session), WT_CONN_LSM_MERGE))
WT_ERR_MSG(session, EINVAL,
"LSM compaction requires active merge threads");
WT_ERR(__wt_seconds(session, &begin));
/*
* Compacting has two distinct phases.
* 1. All in-memory chunks up to and including the current
* current chunk must be flushed. Normally, the flush code
* does not flush the last, in-use chunk, so we set a force
* flag to include that last chunk. We monitor the state of the
* last chunk and periodically push another forced flush work
* unit until it is complete.
* 2. After all flushing is done, we move onto the merging
* phase for compaction. Again, we monitor the state and
* continue to push merge work units until all merging is done.
*/
/* Lock the tree: single-thread compaction. */
WT_ERR(__wt_lsm_tree_writelock(session, lsm_tree));
locked = 1;
/* Clear any merge throttle: compact throws out that calculation. */
lsm_tree->merge_throttle = 0;
lsm_tree->merge_aggressiveness = 0;
progress = lsm_tree->merge_progressing;
/* If another thread started a compact on this tree, we're done. */
if (F_ISSET(lsm_tree, WT_LSM_TREE_COMPACTING))
goto err;
/*
* Set the switch transaction on the current chunk, if it
* hasn't been set before. This prevents further writes, so it
* can be flushed by the checkpoint worker.
*/
if (lsm_tree->nchunks > 0 &&
(chunk = lsm_tree->chunk[lsm_tree->nchunks - 1]) != NULL) {
if (chunk->switch_txn == WT_TXN_NONE)
chunk->switch_txn = __wt_txn_new_id(session);
/*
* If we have a chunk, we want to look for it to be on-disk.
* So we need to add a reference to keep it available.
*/
(void)WT_ATOMIC_ADD4(chunk->refcnt, 1);
ref = 1;
}
locked = 0;
WT_ERR(__wt_lsm_tree_writeunlock(session, lsm_tree));
if (chunk != NULL) {
WT_ERR(__wt_verbose(session, WT_VERB_LSM,
"Compact force flush %s flags 0x%" PRIx32
" chunk %u flags 0x%"
PRIx32, name, lsm_tree->flags, chunk->id, chunk->flags));
flushing = 1;
/*
* Make sure the in-memory chunk gets flushed do not push a
* switch, because we don't want to create a new in-memory
* chunk if the tree is being used read-only now.
*/
WT_ERR(__wt_lsm_manager_push_entry(session,
WT_LSM_WORK_FLUSH, WT_LSM_WORK_FORCE, lsm_tree));
} else {
/*
* If there is no chunk to flush, go straight to the
* compacting state.
*/
compacting = 1;
progress = lsm_tree->merge_progressing;
F_SET(lsm_tree, WT_LSM_TREE_COMPACTING);
WT_ERR(__wt_verbose(session, WT_VERB_LSM,
"COMPACT: Start compacting %s", lsm_tree->name));
}
/* Wait for the work unit queues to drain. */
while (F_ISSET(lsm_tree, WT_LSM_TREE_ACTIVE)) {
/*
* The flush flag is cleared when the chunk has been flushed.
* Continue to push forced flushes until the chunk is on disk.
* Once it is on disk move to the compacting phase.
*/
if (flushing) {
WT_ASSERT(session, chunk != NULL);
if (F_ISSET(chunk, WT_LSM_CHUNK_ONDISK)) {
WT_ERR(__wt_verbose(session,
WT_VERB_LSM,
"Compact flush done %s chunk %u. "
"Start compacting progress %" PRIu64,
name, chunk->id,
lsm_tree->merge_progressing));
(void)WT_ATOMIC_SUB4(chunk->refcnt, 1);
flushing = ref = 0;
compacting = 1;
F_SET(lsm_tree, WT_LSM_TREE_COMPACTING);
progress = lsm_tree->merge_progressing;
} else {
WT_ERR(__wt_verbose(session, WT_VERB_LSM,
"Compact flush retry %s chunk %u",
name, chunk->id));
WT_ERR(__wt_lsm_manager_push_entry(session,
WT_LSM_WORK_FLUSH, WT_LSM_WORK_FORCE,
lsm_tree));
}
}
/*
* The compacting flag is cleared when no merges can be done.
* Ensure that we push through some aggressive merges before
* stopping otherwise we might not do merges that would
* span chunks with different generations.
*/
if (compacting && !F_ISSET(lsm_tree, WT_LSM_TREE_COMPACTING)) {
if (lsm_tree->merge_aggressiveness < 10 ||
(progress < lsm_tree->merge_progressing) ||
lsm_tree->merge_syncing) {
progress = lsm_tree->merge_progressing;
F_SET(lsm_tree, WT_LSM_TREE_COMPACTING);
lsm_tree->merge_aggressiveness = 10;
} else
break;
}
__wt_sleep(1, 0);
WT_ERR(__wt_seconds(session, &end));
if (session->compact->max_time > 0 &&
session->compact->max_time < (uint64_t)(end - begin)) {
WT_ERR(ETIMEDOUT);
}
/*
* Push merge operations while they are still getting work
* done. If we are pushing merges, make sure they are
* aggressive, to avoid duplicating effort.
*/
if (compacting)
#define COMPACT_PARALLEL_MERGES 5
for (i = lsm_tree->queue_ref;
i < COMPACT_PARALLEL_MERGES; i++) {
lsm_tree->merge_aggressiveness = 10;
WT_ERR(__wt_lsm_manager_push_entry(
session, WT_LSM_WORK_MERGE, 0, lsm_tree));
}
}
err:
/* Ensure anything we set is cleared. */
if (ref)
(void)WT_ATOMIC_SUB4(chunk->refcnt, 1);
if (compacting) {
F_CLR(lsm_tree, WT_LSM_TREE_COMPACTING);
lsm_tree->merge_aggressiveness = 0;
}
if (locked)
WT_TRET(__wt_lsm_tree_writeunlock(session, lsm_tree));
WT_TRET(__wt_verbose(session, WT_VERB_LSM,
"Compact %s complete, return %d", name, ret));
__wt_lsm_tree_release(session, lsm_tree);
return (ret);
}
