diff options
Diffstat (limited to 'src/backend/storage/buffer/bufmgr.c')
-rw-r--r-- | src/backend/storage/buffer/bufmgr.c | 31 |
1 files changed, 13 insertions, 18 deletions
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index 667aa0c0c78..67431208e7f 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -2743,12 +2743,10 @@ ExtendBufferedRelShared(BufferManagerRelation bmr, * because mdread doesn't complain about reads beyond EOF (when * zero_damaged_pages is ON) and so a previous attempt to read a block * beyond EOF could have left a "valid" zero-filled buffer. - * Unfortunately, we have also seen this case occurring because of - * buggy Linux kernels that sometimes return an lseek(SEEK_END) result - * that doesn't account for a recent write. In that situation, the - * pre-existing buffer would contain valid data that we don't want to - * overwrite. Since the legitimate cases should always have left a - * zero-filled buffer, complain if not PageIsNew. + * + * This has also been observed when relation was overwritten by + * external process. Since the legitimate cases should always have + * left a zero-filled buffer, complain if not PageIsNew. */ if (existing_id >= 0) { @@ -2778,8 +2776,7 @@ ExtendBufferedRelShared(BufferManagerRelation bmr, ereport(ERROR, (errmsg("unexpected data beyond EOF in block %u of relation %s", existing_hdr->tag.blockNum, - relpath(bmr.smgr->smgr_rlocator, fork).str), - errhint("This has been seen to occur with buggy kernels; consider updating your system."))); + relpath(bmr.smgr->smgr_rlocator, fork).str))); /* * We *must* do smgr[zero]extend before succeeding, else the page @@ -3339,10 +3336,10 @@ UnpinBufferNoOwner(BufferDesc *buf) * BufferSync -- Write out all dirty buffers in the pool. * * This is called at checkpoint time to write out all dirty shared buffers. - * The checkpoint request flags should be passed in. If CHECKPOINT_IMMEDIATE - * is set, we disable delays between writes; if CHECKPOINT_IS_SHUTDOWN, - * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_ALL is set, we write even - * unlogged buffers, which are otherwise skipped. The remaining flags + * The checkpoint request flags should be passed in. If CHECKPOINT_FAST is + * set, we disable delays between writes; if CHECKPOINT_IS_SHUTDOWN, + * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_UNLOGGED is set, we write + * even unlogged buffers, which are otherwise skipped. The remaining flags * currently have no effect here. */ static void @@ -3367,7 +3364,7 @@ BufferSync(int flags) * recovery, we write all dirty buffers. */ if (!((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY | - CHECKPOINT_FLUSH_ALL)))) + CHECKPOINT_FLUSH_UNLOGGED)))) mask |= BM_PERMANENT; /* @@ -4550,11 +4547,9 @@ DropRelationBuffers(SMgrRelation smgr_reln, ForkNumber *forkNum, if (RelFileLocatorBackendIsTemp(rlocator)) { if (rlocator.backend == MyProcNumber) - { - for (j = 0; j < nforks; j++) - DropRelationLocalBuffers(rlocator.locator, forkNum[j], - firstDelBlock[j]); - } + DropRelationLocalBuffers(rlocator.locator, forkNum, nforks, + firstDelBlock); + return; } |