DiskLoc NamespaceDetails::cappedAlloc(const char *ns, int len) {
if ( len > theCapExtent()->length ) {
// the extent check is a way to try and improve performance
uassert( 16328 , str::stream() << "document is larger than capped size "
<< len << " > " << storageSize() , len <= storageSize() );
}
// signal done allocating new extents.
if ( !cappedLastDelRecLastExtent().isValid() )
getDur().writingDiskLoc( cappedLastDelRecLastExtent() ) = DiskLoc();
verify( len < 400000000 );
int passes = 0;
int maxPasses = ( len / 30 ) + 2; // 30 is about the smallest entry that could go in the oplog
if ( maxPasses < 5000 ) {
// this is for bacwards safety since 5000 was the old value
maxPasses = 5000;
}
DiskLoc loc;
// delete records until we have room and the max # objects limit achieved.
/* this fails on a rename -- that is ok but must keep commented out */
//verify( theCapExtent()->ns == ns );
theCapExtent()->assertOk();
DiskLoc firstEmptyExtent;
while ( 1 ) {
if ( _stats.nrecords < maxCappedDocs() ) {
loc = __capAlloc( len );
if ( !loc.isNull() )
break;
}
// If on first iteration through extents, don't delete anything.
if ( !_capFirstNewRecord.isValid() ) {
advanceCapExtent( ns );
if ( _capExtent != _firstExtent )
_capFirstNewRecord.writing().setInvalid();
// else signal done with first iteration through extents.
continue;
}
if ( !_capFirstNewRecord.isNull() &&
theCapExtent()->firstRecord == _capFirstNewRecord ) {
// We've deleted all records that were allocated on the previous
// iteration through this extent.
advanceCapExtent( ns );
continue;
}
if ( theCapExtent()->firstRecord.isNull() ) {
if ( firstEmptyExtent.isNull() )
firstEmptyExtent = _capExtent;
advanceCapExtent( ns );
if ( firstEmptyExtent == _capExtent ) {
maybeComplain( ns, len );
return DiskLoc();
}
continue;
}
DiskLoc fr = theCapExtent()->firstRecord;
theDataFileMgr.deleteRecord(this, ns, fr.rec(), fr, true); // ZZZZZZZZZZZZ
compact();
if( ++passes > maxPasses ) {
StringBuilder sb;
sb << "passes >= maxPasses in NamespaceDetails::cappedAlloc: ns: " << ns
<< ", len: " << len
<< ", maxPasses: " << maxPasses
<< ", _maxDocsInCapped: " << _maxDocsInCapped
<< ", nrecords: " << _stats.nrecords
<< ", datasize: " << _stats.datasize;
msgasserted(10345, sb.str());
}
}
// Remember first record allocated on this iteration through capExtent.
if ( _capFirstNewRecord.isValid() && _capFirstNewRecord.isNull() )
getDur().writingDiskLoc(_capFirstNewRecord) = loc;
return loc;
}
DiskLoc NamespaceDetails::cappedAlloc(const char *ns, int len) {
// signal done allocating new extents.
if ( !cappedLastDelRecLastExtent().isValid() )
getDur().writingDiskLoc( cappedLastDelRecLastExtent() ) = DiskLoc();
verify( len < 400000000 );
int passes = 0;
int maxPasses = ( len / 30 ) + 2; // 30 is about the smallest entry that could go in the oplog
if ( maxPasses < 5000 ) {
// this is for bacwards safety since 5000 was the old value
maxPasses = 5000;
}
DiskLoc loc;
// delete records until we have room and the max # objects limit achieved.
/* this fails on a rename -- that is ok but must keep commented out */
//verify( theCapExtent()->ns == ns );
theCapExtent()->assertOk();
DiskLoc firstEmptyExtent;
while ( 1 ) {
if ( stats.nrecords < max ) {
loc = __capAlloc( len );
if ( !loc.isNull() )
break;
}
// If on first iteration through extents, don't delete anything.
if ( !capFirstNewRecord.isValid() ) {
advanceCapExtent( ns );
if ( capExtent != firstExtent )
capFirstNewRecord.writing().setInvalid();
// else signal done with first iteration through extents.
continue;
}
if ( !capFirstNewRecord.isNull() &&
theCapExtent()->firstRecord == capFirstNewRecord ) {
// We've deleted all records that were allocated on the previous
// iteration through this extent.
advanceCapExtent( ns );
continue;
}
if ( theCapExtent()->firstRecord.isNull() ) {
if ( firstEmptyExtent.isNull() )
firstEmptyExtent = capExtent;
advanceCapExtent( ns );
if ( firstEmptyExtent == capExtent ) {
maybeComplain( ns, len );
return DiskLoc();
}
continue;
}
DiskLoc fr = theCapExtent()->firstRecord;
theDataFileMgr.deleteRecord(ns, fr.rec(), fr, true); // ZZZZZZZZZZZZ
compact();
if( ++passes > maxPasses ) {
log() << "passes ns:" << ns << " len:" << len << " maxPasses: " << maxPasses << '\n';
log() << "passes max:" << max << " nrecords:" << stats.nrecords << " datasize: " << stats.datasize << endl;
massert( 10345 , "passes >= maxPasses in capped collection alloc", false );
}
}
// Remember first record allocated on this iteration through capExtent.
if ( capFirstNewRecord.isValid() && capFirstNewRecord.isNull() )
getDur().writingDiskLoc(capFirstNewRecord) = loc;
return loc;
}
