diff options
Diffstat (limited to 'src/backend/storage/buffer/buf_init.c')
| -rw-r--r-- | src/backend/storage/buffer/buf_init.c | 27 |
1 files changed, 12 insertions, 15 deletions
diff --git a/src/backend/storage/buffer/buf_init.c b/src/backend/storage/buffer/buf_init.c index 6b6a8289ad8..f6500fec89e 100644 --- a/src/backend/storage/buffer/buf_init.c +++ b/src/backend/storage/buffer/buf_init.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/buffer/buf_init.c,v 1.70 2004/12/31 22:00:49 pgsql Exp $ + * $PostgreSQL: pgsql/src/backend/storage/buffer/buf_init.c,v 1.71 2005/02/03 23:29:11 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -73,7 +73,6 @@ long int LocalBufferFlushCount; * aborts, it should only unpin the buffers exactly the number of times it * has pinned them, so that it will not blow away buffers of another * backend. - * */ @@ -120,14 +119,17 @@ InitBufferPool(void) block = BufferBlocks; /* - * link the buffers into a single linked list. This will become - * the LIFO list of unused buffers returned by - * StrategyGetBuffer(). + * Initialize all the buffer headers. */ for (i = 0; i < NBuffers; block += BLCKSZ, buf++, i++) { Assert(ShmemIsValid((unsigned long) block)); + /* + * The bufNext fields link together all totally-unused buffers. + * Subsequent management of this list is done by + * StrategyGetBuffer(). + */ buf->bufNext = i + 1; CLEAR_BUFFERTAG(buf->tag); @@ -142,7 +144,7 @@ InitBufferPool(void) buf->wait_backend_id = 0; } - /* Correct last entry */ + /* Correct last entry of linked list */ BufferDescriptors[NBuffers - 1].bufNext = -1; LWLockRelease(BufMgrLock); @@ -178,7 +180,8 @@ InitBufferPoolAccess(void) /* * Convert shmem offsets into addresses as seen by this process. This - * is just to speed up the BufferGetBlock() macro. + * is just to speed up the BufferGetBlock() macro. It is OK to do this + * without any lock since the data pointers never change. */ for (i = 0; i < NBuffers; i++) BufferBlockPointers[i] = (Block) MAKE_PTR(BufferDescriptors[i].data); @@ -201,14 +204,8 @@ BufferShmemSize(void) /* size of data pages */ size += NBuffers * MAXALIGN(BLCKSZ); - /* size of buffer hash table */ - size += hash_estimate_size(NBuffers * 2, sizeof(BufferLookupEnt)); - - /* size of the shared replacement strategy control block */ - size += MAXALIGN(sizeof(BufferStrategyControl)); - - /* size of the ARC directory blocks */ - size += MAXALIGN(NBuffers * 2 * sizeof(BufferStrategyCDB)); + /* size of stuff controlled by freelist.c */ + size += StrategyShmemSize(); return size; } |