From e0fa771531b92dc096fd5a1580ded3224524fa65 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Mon, 14 Oct 2024 14:10:13 -0400 Subject: [PATCH v20250807 05/11] freelist: Don't track tail of a freelist The freelist tail isn't currently used, making it unnecessary overhead. So just don't do that. --- src/backend/storage/buffer/freelist.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c index 01909be0272..e046526c149 100644 --- a/src/backend/storage/buffer/freelist.c +++ b/src/backend/storage/buffer/freelist.c @@ -40,12 +40,6 @@ typedef struct pg_atomic_uint32 nextVictimBuffer; int firstFreeBuffer; /* Head of list of unused buffers */ - int lastFreeBuffer; /* Tail of list of unused buffers */ - - /* - * NOTE: lastFreeBuffer is undefined when firstFreeBuffer is -1 (that is, - * when the list is empty) - */ /* * Statistics. These counters should be wide enough that they can't @@ -371,8 +365,6 @@ StrategyFreeBuffer(BufferDesc *buf) if (buf->freeNext == FREENEXT_NOT_IN_LIST) { buf->freeNext = StrategyControl->firstFreeBuffer; - if (buf->freeNext < 0) - StrategyControl->lastFreeBuffer = buf->buf_id; StrategyControl->firstFreeBuffer = buf->buf_id; } @@ -509,7 +501,6 @@ StrategyInitialize(bool init) * assume it was previously set up by BufferManagerShmemInit(). */ StrategyControl->firstFreeBuffer = 0; - StrategyControl->lastFreeBuffer = NBuffers - 1; /* Initialize the clock sweep pointer */ pg_atomic_init_u32(&StrategyControl->nextVictimBuffer, 0); -- 2.50.1