// . but now that we may get a list remotely to fix data corruption,
// this may indeed block
bool Msg3::doneScanning ( ) {
QUICKPOLL(m_niceness);
// . did we have any error on any scan?
// . if so, repeat ALL of the scans
g_errno = m_errno;
// 2 retry is the default
int32_t max = 2;
// see if explicitly provided by the caller
if ( m_maxRetries >= 0 ) max = m_maxRetries;
// now use -1 (no max) as the default no matter what
max = -1;
// ENOMEM is particulary contagious, so watch out with it...
if ( g_errno == ENOMEM && m_maxRetries == -1 ) max = 0;
// msg0 sets maxRetries to 2, don't let max stay set to -1
if ( g_errno == ENOMEM && m_maxRetries != -1 ) max = m_maxRetries;
// when thread cannot alloc enough read buf it keeps the read buf
// set to NULL and BigFile.cpp sets g_errno to EBUFTOOSMALL
if ( g_errno == EBUFTOOSMALL && m_maxRetries == -1 ) max = 0;
// msg0 sets maxRetries to 2, don't let max stay set to -1
if ( g_errno == EBUFTOOSMALL && m_maxRetries != -1 ) max = m_maxRetries;
// . if no thread slots available, that hogs up serious memory.
// the size of Msg3 is 82k, so having just 5000 of them is 430MB.
// . i just made Msg3 alloc mem when it needs more than about 2k
// so this problem is greatly reduced, therefore let's keep
// retrying... forever if no thread slots in thread queue since
// we become the thread queue in a way.
if ( g_errno == ENOTHREADSLOTS ) max = -1;
// this is set above if the map has the same consecutive key repeated
// and the read is enormous
if ( g_errno == ECORRUPTDATA ) max = 0;
// usually bad disk failures, don't retry those forever
//if ( g_errno == EIO ) max = 3;
// no, now our hitachis return these even when they're good so
// we have to keep retrying forever
if ( g_errno == EIO ) max = -1;
// count these so we do not take drives offline just because
// kernel ring buffer complains...
if ( g_errno == EIO ) g_numIOErrors++;
// bail early on high priority reads for these errors
if ( g_errno == EDISKSTUCK && m_niceness == 0 ) max = 0;
if ( g_errno == EIO && m_niceness == 0 ) max = 0;
// how does this happen? we should never bail out on a low priority
// disk read... we just wait for it to complete...
if ( g_errno == EDISKSTUCK && m_niceness != 0 ) { char *xx=NULL;*xx=0;}
// on I/O, give up at call it corrupt after a while. some hitachis
// have I/O errros on little spots, like gk88, maybe we can fix him
if ( g_errno == EIO && m_retryNum >= 5 ) {
m_errno = ECORRUPTDATA;
m_hadCorruption = true;
// do not do any retries any more
max = 0;
}
// convert m_errno to ECORRUPTDATA if it is EBUFTOOSMALL and the
// max of the bytesToRead are over 500MB.
// if bytesToRead was ludicrous, then assume that the data file
// was corrupted, the map was regenerated and it patched
// over the corrupted bits which were 500MB or more in size.
// we cannot practically allocate that much, so let's just
// give back an empty buffer. treat it like corruption...
// the way it patches is to store the same key over all the corrupted
// pages, which can get pretty big. so if you read a range with that
// key you will be hurting!!
// this may be the same scenario as when the rdbmap has consecutive
// same keys. see above where we set m_errno to ECORRUPTDATA...
if ( g_errno == EBUFTOOSMALL ) {
int32_t biggest = 0;
for ( int32_t i = 0 ; i < m_numFileNums ; i++ ) {
if ( m_scans[i].m_bytesToRead < biggest ) continue;
biggest = m_scans[i].m_bytesToRead;
}
if ( biggest > 500000000 ) {
log("db: Max read size was %" PRId32" > 500000000. Assuming "
"corrupt data in data file.",biggest);
m_errno = ECORRUPTDATA;
m_hadCorruption = true;
// do not do any retries on this, the read was > 500MB
max = 0;
}
}
// if shutting down gb then limit to 20 so we can shutdown because
// it can't shutdown until all threads are out of the queue i think
if ( g_process.m_mode == EXIT_MODE && max < 0 ) {
//log("msg3: forcing retries to 0 because shutting down");
max = 0;
}
// get base, returns NULL and sets g_errno to ENOCOLLREC on error
RdbBase *base = getRdbBase( m_rdbId, m_collnum );
if ( ! base ) {
return true;
}
// this really slows things down because it blocks the cpu so
// leave it out for now
#ifdef GBSANITYCHECK
// check for corruption here, do not do it again in Msg5 if we pass
if ( ! g_errno ) { // && g_conf.m_doErrorCorrection ) {
int32_t i;
for ( i = 0 ; i < m_numFileNums ; i++ )
if ( ! m_lists[i].checkList_r ( false, false ) ) break;
if ( i < m_numFileNums ) {
g_errno = ECORRUPTDATA;
m_errno = ECORRUPTDATA;
max = g_conf.m_corruptRetries; // try 100 times
log("db: Encountered corrupt list in file %s.",
base->getFile(m_fileNums[i])->getFilename());
}
else
m_listsChecked = true;
}
#endif
// try to fix this error i've seen
if ( g_errno == EBADENGINEER && max == -1 )
max = 100;
// . if we had a ETRYAGAIN error, then try again now
// . it usually means the whole file or a part of it was deleted
// before we could finish reading it, so we should re-read all now
// . RdbMerge deletes BigFiles after it merges them and also chops
// off file heads
// . now that we have threads i'd imagine we'd get EBADFD or something
// . i've also seen "illegal seek" as well
if ( m_errno && (m_retryNum < max || max < 0) &&
// this will complete in due time, we can't call a sleep wrapper
// on it because the read is really still pending...
m_errno != EDISKSTUCK ) {
// print the error
static time_t s_time = 0;
time_t now = getTime();
if ( now - s_time > 5 || g_errno != ENOTHREADSLOTS ) {
log("net: Had error reading %s: %s. Retrying. "
"(retry #%" PRId32")",
base->m_dbname,mstrerror(m_errno) , m_retryNum );
s_time = now;
}
// send email alert if in an infinite loop, but don't send
// more than once every 2 hours
static int32_t s_lastSendTime = 0;
if ( m_retryNum == 100 && getTime() - s_lastSendTime > 3600*2){
// remove this for now it is going off all the time
//g_pingServer.sendEmail(NULL,//g_hostdb.getMyHost(),
// "100 read retries",true);
s_lastSendTime = getTime();
}
// clear g_errno cuz we should for call to readList()
g_errno = 0;
// free the list buffer since if we have 1000 Msg3s retrying
// it will totally use all of our memory
for ( int32_t i = 0 ; i < m_numChunks ; i++ )
m_lists[i].destructor();
// count retries
m_retryNum++;
// backoff scheme, wait 100ms more each time
int32_t wait ;
if ( m_retryNum == 1 ) wait = 10;
else wait = 200 * m_retryNum;
// . don't wait more than 10 secs between tries
// . i've seen gf0 and gf16 get mega saturated
if ( wait > 10000 ) wait = 10000;
// wait 500 ms
if ( g_loop.registerSleepCallback ( wait , // ms
this ,
doneSleepingWrapper3,
m_niceness))
return false;
// otherwise, registration failed
log(
"net: Failed to register sleep callback for retry. "
"Abandoning read. This is bad.");
// return, g_errno should be set
g_errno = EBUFTOOSMALL;
m_errno = EBUFTOOSMALL;
return true;
}
// if we got an error and should not retry any more then give up
if ( g_errno ) {
log(
"net: Had error reading %s: %s. Giving up after %" PRId32" "
"retries.",
base->m_dbname,mstrerror(g_errno) , m_retryNum );
return true;
}
// note it if the retry finally worked
if ( m_retryNum > 0 )
log(LOG_INFO,"disk: Read succeeded after retrying %" PRId32" times.",
(int32_t)m_retryNum);
// count total bytes for logging
int32_t count = 0;
// . constrain all lists to make merging easier
// . if we have only one list, then that's nice cuz the constrain
// will allow us to send it right away w/ zero copying
// . if we have only 1 list, it won't be merged into a final list,
// that is, we'll just set m_list = &m_lists[i]
for ( int32_t i = 0 ; i < m_numFileNums ; i++ ) {
QUICKPOLL(m_niceness);
// count total bytes for logging
count += m_lists[i].getListSize();
// . hint offset is relative to the offset of first key we read
// . if that key was only 6 bytes RdbScan shift the list buf
// down 6 bytes to make the first key 12 bytes... a
// requirement for all RdbLists
// . don't inc it, though, if it was 0, pointing to the start
// of the list because our shift won't affect that
if ( m_scans[i].m_shifted == 6 && m_hintOffsets[i] > 0 )
m_hintOffsets[i] += 6;
// posdb double compression
if ( m_scans[i].m_shifted == 12 && m_hintOffsets[i] > 0 )
m_hintOffsets[i] += 12;
// . don't constrain on minRecSizes here because it may
// make our endKey smaller, which will cause problems
// when Msg5 merges these lists.
// . If all lists have different endKeys RdbList's merge
// chooses the min and will merge in recs beyond that
// causing a bad list BECAUSE we don't check to make
// sure that recs we are adding are below the endKey
// . if we only read from one file then constrain based
// on minRecSizes so we can send the list back w/o merging
// OR if just merging with RdbTree's list
int32_t mrs ;
// . constrain to m_minRecSizesOrig, not m_minRecSizes cuz
// that could be adjusted by compensateForNegativeRecs()
// . but, really, they should be the same if we only read from
// the root file
if ( m_numFileNums == 1 ) mrs = m_minRecSizesOrig;
else mrs = -1;
// . this returns false and sets g_errno on error
// . like if data is corrupt
BigFile *ff = base->getFile(m_fileNums[i]);
// if we did a merge really quick and delete one of the
// files we were reading, i've seen 'ff' be NULL
char *filename = "lostfilename";
if ( ff ) filename = ff->getFilename();
// compute cache info
RdbCache *rpc = getDiskPageCache ( m_rdbId );
if ( ! m_allowPageCache ) rpc = NULL;
int64_t vfd ;
if ( ff ) vfd = ff->getVfd();
key192_t ck ;
if ( ff )
ck = makeCacheKey ( vfd ,
m_scans[i].m_offset ,
m_scans[i].m_bytesToRead );
if ( m_validateCache && ff && rpc && vfd != -1 ) {
bool inCache;
char *rec; int32_t recSize;
inCache = rpc->getRecord ( (collnum_t)0 , // collnum
(char *)&ck ,
&rec ,
&recSize ,
true , // copy?
-1 , // maxAge, none
true ); // inccounts?
if ( inCache &&
// 1st byte is RdbScan::m_shifted
( m_lists[i].m_listSize != recSize-1 ||
memcmp ( m_lists[i].m_list , rec+1,recSize-1) ||
*rec != m_scans[i].m_shifted ) ) {
log("msg3: cache did not validate");
char *xx=NULL;*xx=0;
}
mfree ( rec , recSize , "vca" );
}
///////
//
// STORE IN PAGE CACHE
//
///////
// store what we read in the cache. don't bother storing
// if it was a retry, just in case something strange happened.
// store pre-constrain call is more efficient.
if ( m_retryNum<=0 && ff && rpc && vfd != -1 &&
! m_scans[i].m_inPageCache )
rpc->addRecord ( (collnum_t)0 , // collnum
(char *)&ck ,
// rec1 is this little thingy
&m_scans[i].m_shifted,
1,
// rec2
m_lists[i].getList() ,
m_lists[i].getListSize() ,
0 ); // timestamp. 0 = now
QUICKPOLL(m_niceness);
// if from our 'page' cache, no need to constrain
if ( ! m_lists[i].constrain ( m_startKey ,
m_constrainKey , // m_endKey
mrs , // m_minRecSizes
m_hintOffsets[i] ,
//m_hintKeys [i] ,
&m_hintKeys [i*m_ks] ,
filename,//ff->getFilename() ,
m_niceness ) ) {
log("net: Had error while constraining list read from "
"%s: %s/%s. vfd=%" PRId32" parts=%" PRId32". "
"This is likely caused by corrupted "
"data on disk.",
mstrerror(g_errno), ff->getDir(),
ff->getFilename(), ff->m_vfd ,
(int32_t)ff->m_numParts );
continue;
}
}
// print the time
if ( g_conf.m_logTimingDb ) {
int64_t now = gettimeofdayInMilliseconds();
int64_t took = now - m_startTime;
log(LOG_TIMING,
"net: Took %" PRId64" ms to read %" PRId32" lists of %" PRId32" bytes total"
" from %s (niceness=%" PRId32").",
took,m_numFileNums,count,base->m_dbname,m_niceness);
}
return true;
}
// . return false if blocked, true otherwise
// . set g_errno on error
// . read list of keys in [startKey,endKey] range
// . read at least "minRecSizes" bytes of keys in that range
// . the "m_endKey" of resulting, merged list may have a smaller endKey
// than the argument, "endKey" due to limitation by "minRecSizes"
// . resulting list will contain ALL keys between ITS [m_startKey,m_endKey]
// . final merged list "should" try to have a size of at least "minRecSizes"
// but due to negative/postive rec elimination may be less
// . the endKey of the lists we read may be <= "endKey" provided
// . we try to shrink the endKey if minRecSizes is >= 0 in order to
// avoid excessive reading
// . by shrinking the endKey we cannot take into account the size of deleted
// records, so therefore we may fall short of "minRecSizes" in actuality,
// in fact, the returned list may even be empty with a shrunken endKey
// . we merge all lists read from disk into the provided "list"
// . caller should call Msg3.getList(int32_t i) and Msg3:getNumLists() to retrieve
// . this makes the query engine faster since we don't need to merge the docIds
// and can just send them across the network separately and they will be
// hashed into IndexTable's table w/o having to do time-wasting merging.
// . caller can specify array of filenums to read from so incremental syncing
// in Sync class can just read from titledb*.dat files that were formed
// since the last sync point.
bool Msg3::readList ( char rdbId ,
collnum_t collnum ,
const char *startKeyArg ,
const char *endKeyArg ,
int32_t minRecSizes , // max size of scan
int32_t startFileNum , // first file to scan
int32_t numFiles , // rel. to startFileNum
void *state , // for callback
void (* callback ) ( void *state ) ,
int32_t niceness ,
int32_t retryNum ,
int32_t maxRetries ,
bool compensateForMerge ,
bool justGetEndKey ,
bool allowPageCache ,
bool hitDisk ) {
// set this to true to validate
m_validateCache = false;//true;
// clear, this MUST be done so if we return true g_errno is correct
g_errno = 0;
// assume lists are not checked for corruption
m_listsChecked = false;
// warn
if ( minRecSizes < -1 ) {
log(LOG_LOGIC,"db: Msg3 got minRecSizes of %" PRId32", changing "
"to -1.",minRecSizes);
minRecSizes = -1;
}
// reset m_alloc and data in all lists in case we are a re-call
reset();
// warning
if ( collnum < 0 ) log(LOG_LOGIC,"net: NULL collection. msg3.");
// remember the callback
m_rdbId = rdbId;
m_collnum = collnum;
m_callback = callback;
m_state = state;
m_niceness = niceness;
m_numScansCompleted = 0;
m_retryNum = retryNum;
m_maxRetries = maxRetries;
m_compensateForMerge = compensateForMerge;
m_allowPageCache = allowPageCache;
m_hitDisk = hitDisk;
m_hadCorruption = false;
// get keySize of rdb
m_ks = getKeySizeFromRdbId ( m_rdbId );
// reset the group error
m_errno = 0;
// . reset all our lists
// . these are reset in call the RdbScan::setRead() below
//for ( int32_t i = 0 ; i < MAX_RDB_FILES ; i++ ) m_lists[i].reset();
// . ensure startKey last bit clear, endKey last bit set
// . no! this warning is now only in Msg5
// . if RdbMerge is merging some files, not involving the root
// file, then we can expect to get a lot of unmatched negative recs.
// . as a consequence, our endKeys may often be negative. This means
// it may not annihilate with the positive key, but we should only
// miss like this at the boundaries of the lists we fetch.
// . so in that case RdbList::merge will stop merging once the
// minRecSizes limit is reached even if it means ending on a negative
// rec key
//if ( (startKey.n0 & 0x01) == 0x01 )
if ( !KEYNEG(startKeyArg) )
log(LOG_REMIND,"net: msg3: StartKey lastbit set.");
if ( KEYNEG(endKeyArg) )
log(LOG_REMIND,"net: msg3: EndKey lastbit clear.");
// declare vars here becaues of 'goto skip' below
int32_t mergeFileNum = -1 ;
int32_t max ;
// get base, returns NULL and sets g_errno to ENOCOLLREC on error
RdbBase *base = getRdbBase( m_rdbId, m_collnum );
if ( ! base ) {
return true;
}
// store the file numbers in the array, these are the files we read
m_numFileNums = 0;
// save startFileNum here, just for recall
m_startFileNum = startFileNum;
m_numFiles = numFiles;
// . if we have a merge going on, we may have to change startFileNum
// . if some files get unlinked because merge completes then our
// reads will detect the error and loop back here
// . we launch are reads right after this without giving up the cpu
// and we use file descriptors, so any changes to Rdb::m_files[]
// should not hurt us
// . WARNING: just make sure you don't lose control of cpu until after
// you call RdbScan::set()
// . we use hasMergeFile() instead of isMerging() because he may not
// be merging cuz he got suspended or he restarted and
// hasn't called attemptMerge() yet, but he may still contain it
if ( g_conf.m_logDebugQuery )
log(LOG_DEBUG,
"net: msg3: "
"c=%" PRId32" hmf=%" PRId32" sfn=%" PRId32" msfn=%" PRId32" nf=%" PRId32" db=%s.",
(int32_t)compensateForMerge,(int32_t)base->hasMergeFile(),
(int32_t)startFileNum,(int32_t)base->m_mergeStartFileNum-1,
(int32_t)numFiles,base->m_dbname);
int32_t pre = -10;
if ( compensateForMerge && base->hasMergeFile() &&
startFileNum >= base->m_mergeStartFileNum - 1 &&
(startFileNum > 0 || numFiles != -1) ) {
// now also include the file being merged into, but only
// if we are reading from a file being merged...
if ( startFileNum < base->m_mergeStartFileNum +
base->m_numFilesToMerge - 1 )
//m_fileNums [ m_numFileNums++ ] =
// base->m_mergeStartFileNum - 1;
pre = base->m_mergeStartFileNum - 1;
// debug msg
if ( g_conf.m_logDebugQuery )
log(LOG_DEBUG,
"net: msg3: startFileNum from %" PRId32" to %" PRId32" (mfn=%" PRId32")",
startFileNum,startFileNum+1,mergeFileNum);
// if merge file was inserted before us, inc our file number
startFileNum++;
}
// adjust num files if we need to, as well
if ( compensateForMerge && base->hasMergeFile() &&
startFileNum < base->m_mergeStartFileNum - 1 &&
numFiles != -1 &&
startFileNum + numFiles - 1 >= base->m_mergeStartFileNum - 1 ) {
// debug msg
if ( g_conf.m_logDebugQuery )
log(LOG_DEBUG,"net: msg3: numFiles up one.");
// if merge file was inserted before us, inc our file number
numFiles++;
}
// . how many rdb files does this base have?
// . IMPORTANT: this can change since files are unstable because they
// might have all got merged into one!
// . so do this check to make sure we're safe... especially if
// there was an error before and we called readList() on ourselves
max = base->getNumFiles();
// -1 means we should scan ALL the files in the base
if ( numFiles == -1 ) numFiles = max;
// limit it by startFileNum, however
if ( numFiles > max - startFileNum ) numFiles = max - startFileNum;
// set g_errno and return true if it is < 0
if ( numFiles < 0 ) {
log(LOG_LOGIC,
"net: msg3: readList: numFiles = %" PRId32" < 0 (max=%" PRId32")(sf=%" PRId32")",
numFiles , max , startFileNum );
g_errno = EBADENGINEER;
// force core dump
char *xx=NULL;*xx=0;
return true;
}
// . allocate buffer space
// . m_scans, m_startpg, m_endpg, m_hintKeys, m_hintOffsets,
// m_fileNums, m_lists
int32_t chunk = sizeof(RdbScan) + // m_scans
4 + // m_startpg
4 + // m_endpg
//sizeof(key_t) + // m_hintKeys
m_ks + // m_hintKeys
4 + // m_hintOffsets
4 + // m_fileNums
sizeof(RdbList) ; // m_lists
int32_t nn = numFiles;
if ( pre != -10 ) nn++;
m_numChunks = nn;
int32_t need = nn * (chunk);
m_alloc = m_buf;
if ( need > (int32_t)MSG3_BUF_SIZE ) {
m_allocSize = need;
m_alloc = (char *)mcalloc ( need , "Msg3" );
if ( ! m_alloc ) {
log("disk: Could not allocate %" PRId32" bytes read "
"structures to read %s.",need,base->m_dbname);
return true;
}
}
char *p = m_alloc;
m_scans = (RdbScan *)p; p += nn * sizeof(RdbScan);
m_startpg = (int32_t *)p; p += nn * 4;
m_endpg = (int32_t *)p; p += nn * 4;
//m_hintKeys = (key_t *)p; p += nn * sizeof(key_t);
m_hintKeys = (char *)p; p += nn * m_ks;
m_hintOffsets = (int32_t *)p; p += nn * 4;
m_fileNums = (int32_t *)p; p += nn * 4;
m_lists = (RdbList *)p; p += nn * sizeof(RdbList);
// sanity check
if ( p - m_alloc != need ) {
log(LOG_LOGIC,"disk: Bad malloc in Msg3.cpp.");
char *xx = NULL; *xx = 0;
}
// call constructors
for ( int32_t i = 0 ; i < nn ; i++ ) m_lists[i].constructor();
// make fix from up top
if ( pre != -10 ) m_fileNums [ m_numFileNums++ ] = pre;
// store them all
for ( int32_t i = startFileNum ; i < startFileNum + numFiles ; i++ )
m_fileNums [ m_numFileNums++ ] = i;
// . remove file nums that are being unlinked after a merge now
// . keep it here (below skip: label) so sync point reads can use it
int32_t n = 0;
for ( int32_t i = 0 ; i < m_numFileNums ; i++ ) {
// skip those that are being unlinked after the merge
if ( base->m_isUnlinking &&
m_fileNums[i] >= base->m_mergeStartFileNum &&
m_fileNums[i] < base->m_mergeStartFileNum +
base->m_numFilesToMerge )
continue;
// otherwise, keep it
m_fileNums[n++] = m_fileNums[i];
}
m_numFileNums = n;
// . if root file is being merged, he's file #0, & root file is file #1
// . this is a hack so caller gets what he wants
//if ( startFileNum == 0 && base->getFileId(0) == 0 && numFiles == 1 )
// numFiles = 2;
// remember the file range we should scan
m_numScansStarted = 0;
m_numScansCompleted = 0;
//m_startKey = startKey;
//m_endKey = endKey;
//m_constrainKey = endKey; // set in case justGetEndKey is true
KEYSET(m_startKey,startKeyArg,m_ks);
KEYSET(m_endKey,endKeyArg,m_ks);
KEYSET(m_constrainKey,endKeyArg,m_ks);//set incase justGetEndKey istrue
m_minRecSizes = minRecSizes;
m_compensateForMerge = compensateForMerge;
// bail if 0 files to scan -- no! need to set startKey/endKey
if ( numFiles == 0 ) return true;
// don't read anything if endKey < startKey
//if ( m_startKey > m_endKey ) return true;
if ( KEYCMP(m_startKey,m_endKey,m_ks)>0 ) return true;
// keep the original in tact in case g_errno == ETRYAGAIN
//m_endKeyOrig = endKey;
KEYSET(m_endKeyOrig,endKeyArg,m_ks);
m_minRecSizesOrig = minRecSizes;
// start reading at this key
m_fileStartKey = startKeyArg;
// start the timer, keep it fast for clusterdb though
if ( g_conf.m_logTimingDb ) m_startTime = gettimeofdayInMilliseconds();
// translate base to an id, for the sake of m_msg0
//char baseId = m_msg0->getRdbId ( base );
// map ptrs
RdbMap **maps = base->getMaps();
// . we now boost m_minRecSizes to account for negative recs
// . but not if only reading one list, cuz it won't get merged and
// it will be too big to send back
if ( m_numFileNums > 1 ) compensateForNegativeRecs ( base );
// . often endKey is too big for an efficient read of minRecSizes bytes
// because we end up reading too much from all the files
// . this will set m_startpg[i], m_endpg[i] for each RdbScan/RdbFile
// to ensure we read "minRecSizes" worth of records, not much more
// . returns the new endKey for all ranges
// . now this just overwrites m_endKey
//m_endKey = setPageRanges ( base ,
setPageRanges ( base ,
m_fileNums ,
m_numFileNums ,
m_fileStartKey , // start reading @ key
m_endKey , // stop reading @ key
m_minRecSizes );
// . NEVER let m_endKey be a negative key, because it will
// always be unmatched, since delbit is cleared
// . adjusting it here ensures our generated hints are valid
// . we will use this key to call constrain() with
//m_constrainKey = m_endKey;
//if ( ( m_constrainKey.n0 & 0x01) == 0x00 )
// m_constrainKey -= (uint32_t)1;
KEYSET(m_constrainKey,m_endKey,m_ks);
if ( KEYNEG(m_constrainKey) )
KEYSUB(m_constrainKey,m_ks);
// Msg5 likes to get the endkey for getting the list from the tree
if ( justGetEndKey ) return true;
// sanity check
if ( m_numFileNums > nn ) {
log(LOG_LOGIC,"disk: Failed sanity check in Msg3.");
char *xx = NULL; *xx = 0;
}
// debug msg
//log("msg3 getting list (msg5=%" PRIu32")",m_state);
// . MDW removed this -- go ahead an end on a delete key
// . RdbMerge might not pick it up this round, but oh well
// . so we can have both positive and negative co-existing in same file
// make sure the last bit is set so we don't end on a delete key
//m_endKey.n0 |= 0x01LL;
// . now start reading/scanning the files
// . our m_scans array starts at 0
for ( int32_t i = 0 ; i < m_numFileNums ; i++ ) {
// get the page range
//int32_t p1 = m_startpg [ i ];
//int32_t p2 = m_endpg [ i ];
//#ifdef GBSANITYCHECK
int32_t fn = m_fileNums[i];
// this can happen somehow!
if ( fn < 0 ) {
log(LOG_LOGIC,"net: msg3: fn=%" PRId32". Bad engineer.",fn);
continue;
}
// sanity check
if ( i > 0 && m_fileNums[i-1] >= fn ) {
log(LOG_LOGIC,
"net: msg3: files must be read in order "
"from oldest to newest so RdbList::indexMerge_r "
"works properly. Otherwise, corruption will "
"result. ");
char *xx = NULL; *xx = 0;
return true;
}
// . sanity check?
// . no, we must get again since we turn on endKey's last bit
int32_t p1 , p2;
maps[fn]->getPageRange ( m_fileStartKey ,
m_endKey ,
&p1 ,
&p2 ,
NULL );
//if ( p1 != p1c || p2 != p2c ) {
// fprintf(stderr,"Msg3::bad page range\n");
// sleep(50000);
//}
// sanity check, each endpg's key should be > endKey
//if ( p2 < maps[fn]->getNumPages() &&
// maps[fn]->getKey ( p2 ) <= m_endKey ) {
// fprintf(stderr,"Msg3::bad page range 2\n");
// sleep(50000);
//}
//#endif
//int32_t p1 , p2;
//maps[fn]->getPageRange (startKey,endKey,minRecSizes,&p1,&p2);
// now get some read info
int64_t offset = maps[fn]->getAbsoluteOffset ( p1 );
int32_t bytesToRead = maps[fn]->getRecSizes ( p1, p2, false);
// max out the endkey for this list
// debug msg
//#ifdef _DEBUG_
//if ( minRecSizes == 2000000 )
//log("Msg3:: reading %" PRId32" bytes from file #%" PRId32,bytesToRead,i);
//#endif
// inc our m_numScans
m_numScansStarted++;
// . keep stats on our disk accesses
// . count disk seeks (assuming no fragmentation)
// . count disk bytes read
if ( bytesToRead > 0 ) {
base->m_rdb->didSeek ( );
base->m_rdb->didRead ( bytesToRead );
}
// . the startKey may be different for each RdbScan class
// . RdbLists must have all keys within their [startKey,endKey]
// . therefore set startKey individually from first page in map
// . this endKey must be >= m_endKey
// . this startKey must be < m_startKey
//key_t startKey = maps[fn]->getKey ( p1 );
//key_t endKey = maps[fn]->getKey ( p2 );
char startKey2 [ MAX_KEY_BYTES ];
char endKey2 [ MAX_KEY_BYTES ];
maps[fn]->getKey ( p1 , startKey2 );
maps[fn]->getKey ( p2 , endKey2 );
//char *startKey = maps[fn]->getKeyPtr ( p1 );
//char *endKey = maps[fn]->getKeyPtr ( p2 );
// store in here
m_startpg [ i ] = p1;
m_endpg [ i ] = p2;
// . we read UP TO that endKey, so reduce by 1
// . but iff p2 is NOT the last page in the map/file
// . maps[fn]->getKey(lastPage) will return the LAST KEY
// and maps[fn]->getOffset(lastPage) the length of the file
//if ( maps[fn]->getNumPages()!=p2) endKey -=(uint32_t)1;
if ( maps[fn]->getNumPages() != p2 ) KEYSUB(endKey2,m_ks);
// otherwise, if we're reading all pages, then force the
// endKey to virtual inifinite
//else endKey.setMax();
else KEYMAX(endKey2,m_ks);
// . set up the hints
// . these are only used if we are only reading from 1 file
// . these are used to call constrain() so we can constrain
// the end of the list w/o looping through all the recs
// in the list
int32_t h2 = p2 ;
// decrease by one page if we're on the last page
if ( h2 > p1 && maps[fn]->getNumPages() == h2 ) h2--;
// . decrease hint page until key is <= endKey on that page
// AND offset is NOT -1 because the old way would give
// us hints passed the endkey
// . also decrease so we can constrain on minRecSizes in
// case we're the only list being read
// . use >= m_minRecSizes instead of >, otherwise we may
// never be able to set "size" in RdbList::constrain()
// because "p" could equal "maxPtr" right away
while ( h2 > p1 &&
//( maps[fn]->getKey (h2) > m_constrainKey ||
(KEYCMP(maps[fn]->getKeyPtr(h2),m_constrainKey,m_ks)>0||
maps[fn]->getOffset(h2) == -1 ||
maps[fn]->getAbsoluteOffset(h2) - offset >=
m_minRecSizes ) )
h2--;
// now set the hint
m_hintOffsets [ i ] = maps[fn]->getAbsoluteOffset ( h2 ) -
maps[fn]->getAbsoluteOffset ( p1 ) ;
//m_hintKeys [ i ] = maps[fn]->getKey ( h2 );
KEYSET(&m_hintKeys[i*m_ks],maps[fn]->getKeyPtr(h2),m_ks);
// reset g_errno before calling setRead()
g_errno = 0;
// . this fix is now in RdbList::checklist_r()
// . we can now have dup keys, so, we may read in
// a rec with key "lastMinKey" even though we don't read
// in the first key on the end page, so don't subtract 1...
//if ( endKey != m_endKeyOrig )
// endKey += (uint32_t) 1;
// timing debug
if ( g_conf.m_logTimingDb )
log(LOG_TIMING,
"net: msg: reading %" PRId32" bytes from %s file #%" PRId32" "
"(niceness=%" PRId32")",
bytesToRead,base->m_dbname,i,m_niceness);
// log huge reads, those hurt us
if ( bytesToRead > 150000000 ) {
logf(LOG_INFO,"disk: Reading %" PRId32" bytes at offset %" PRId64" "
"from %s.",
bytesToRead,offset,base->m_dbname);
}
// if any keys in the map are the same report corruption
char tmpKey [16];
char lastTmpKey[16];
int32_t ccount = 0;
if ( bytesToRead > 10000000 &&
bytesToRead / 2 > m_minRecSizes &&
base->m_fixedDataSize >= 0 ) {
for ( int32_t pn = p1 ; pn <= p2 ; pn++ ) {
maps[fn]->getKey ( pn , tmpKey );
if ( KEYCMP(tmpKey,lastTmpKey,m_ks) == 0 )
ccount++;
gbmemcpy(lastTmpKey,tmpKey,m_ks);
}
}
if ( ccount > 10 ) {
logf(LOG_INFO,"disk: Reading %" PRId32" bytes from %s file #"
"%" PRId32" when min "
"required is %" PRId32". Map is corrupt and has %" PRId32" "
"identical consecutive page keys because the "
"map was \"repaired\" because out of order keys "
"in the index.",
(int32_t)bytesToRead,
base->m_dbname,fn,
(int32_t)m_minRecSizes,
(int32_t)ccount);
m_numScansCompleted++;
m_errno = ECORRUPTDATA;
m_hadCorruption = true;
//m_maxRetries = 0;
break;
}
////////
//
// try to get from PAGE CACHE
//
////////
BigFile *ff = base->getFile(m_fileNums[i]);
RdbCache *rpc = getDiskPageCache ( m_rdbId );
if ( ! m_allowPageCache ) rpc = NULL;
// . vfd is unique 64 bit file id
// . if file is opened vfd is -1, only set in call to open()
int64_t vfd = ff->getVfd();
key192_t ck = makeCacheKey ( vfd , offset, bytesToRead);
char *rec; int32_t recSize;
bool inCache = false;
if ( rpc && vfd != -1 && ! m_validateCache )
inCache = rpc->getRecord ( (collnum_t)0 , // collnum
(char *)&ck ,
&rec ,
&recSize ,
true , // copy?
-1 , // maxAge, none
true ); // inccounts?
m_scans[i].m_inPageCache = false;
if ( inCache ) {
m_scans[i].m_inPageCache = true;
m_numScansCompleted++;
// now we have to store this value, 6 or 12 so
// we can modify the hint appropriately
m_scans[i].m_shifted = *rec;
m_lists[i].set ( rec +1,
recSize-1 ,
rec , // alloc
recSize , // allocSize
startKey2 ,
endKey2 ,
base->m_fixedDataSize ,
true , // owndata
base->useHalfKeys() ,
getKeySizeFromRdbId ( m_rdbId ) );
continue;
}
// . do the scan/read of file #i
// . this returns false if blocked, true otherwise
// . this will set g_errno on error
bool done = m_scans[i].setRead (base->getFile(m_fileNums[i]),
base->m_fixedDataSize ,
offset ,
bytesToRead ,
startKey2 ,
endKey2 ,
m_ks ,
&m_lists[i] ,
this ,
doneScanningWrapper ,
base->useHalfKeys() ,
m_rdbId,
m_niceness ,
m_allowPageCache ,
m_hitDisk ) ;
// . damn, usually the above will indirectly launch a thread
// to do the reading, but it sets g_errno to EINTR,
// "interrupted system call"!
// . i guess the thread does the read w/o blocking and then
// queues the signal on g_loop's queue before it exits
// . try ignoring, and keep going
if ( g_errno == EINTR ) {
log("net: Interrupted system call while reading file. "
"Ignoring.");
g_errno = 0;
}
// debug msg
//fprintf(stderr,"Msg3:: reading %" PRId32" bytes from file #%" PRId32","
// "done=%" PRId32",offset=%" PRId64",g_errno=%s,"
// "startKey=n1=%" PRIu32",n0=%" PRIu64", "
// "endKey=n1=%" PRIu32",n0=%" PRIu64"\n",
// bytesToRead,i,(int32_t)done,offset,mstrerror(g_errno),
// m_startKey,m_endKey);
//if ( bytesToRead == 0 )
// fprintf(stderr,"shit\n");
// if it did not block then it completed, so count it
if ( done ) m_numScansCompleted++;
// break on an error, and remember g_errno in case we block
if ( g_errno && g_errno != ENOTHREADSLOTS ) {
int32_t tt = LOG_WARN;
if ( g_errno == EFILECLOSED ) tt = LOG_INFO;
log(tt,"disk: Reading %s had error: %s.",
base->m_dbname, mstrerror(g_errno));
m_errno = g_errno;
break;
}
}
// debug test
//if ( rand() % 100 <= 10 ) m_errno = EIO;
// if we blocked, return false
if ( m_numScansCompleted < m_numScansStarted ) return false;
// . if all scans completed without blocking then wrap it up & ret true
// . doneScanning may now block if it finds data corruption and must
// get the list remotely
return doneScanning();
}