diff options
Diffstat (limited to 'src/backend/storage/buffer/bufmgr.c')
| -rw-r--r-- | src/backend/storage/buffer/bufmgr.c | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index 246f31bfe14..c0702789446 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -116,7 +116,7 @@ static int rnode_comparator(const void *p1, const void *p2); * PrefetchBuffer -- initiate asynchronous read of a block of a relation * * This is named by analogy to ReadBuffer but doesn't actually allocate a - * buffer. Instead it tries to ensure that a future ReadBuffer for the given + * buffer. Instead it tries to ensure that a future ReadBuffer for the given * block will not be delayed by the I/O. Prefetching is optional. * No-op if prefetching isn't compiled in. */ @@ -206,7 +206,7 @@ ReadBuffer(Relation reln, BlockNumber blockNum) * Assume when this function is called, that reln has been opened already. * * In RBM_NORMAL mode, the page is read from disk, and the page header is - * validated. An error is thrown if the page header is not valid. (But + * validated. An error is thrown if the page header is not valid. (But * note that an all-zero page is considered "valid"; see PageIsVerified().) * * RBM_ZERO_ON_ERROR is like the normal mode, but if the page header is not @@ -214,7 +214,7 @@ ReadBuffer(Relation reln, BlockNumber blockNum) * for non-critical data, where the caller is prepared to repair errors. * * In RBM_ZERO mode, if the page isn't in buffer cache already, it's filled - * with zeros instead of reading it from disk. Useful when the caller is + * with zeros instead of reading it from disk. Useful when the caller is * going to fill the page from scratch, since this saves I/O and avoids * unnecessary failure if the page-on-disk has corrupt page headers. * Caution: do not use this mode to read a page that is beyond the relation's @@ -371,7 +371,7 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, * This can happen 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 + * 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 @@ -597,7 +597,7 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, /* * Didn't find it in the buffer pool. We'll have to initialize a new - * buffer. Remember to unlock the mapping lock while doing the work. + * buffer. Remember to unlock the mapping lock while doing the work. */ LWLockRelease(newPartitionLock); @@ -607,7 +607,7 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, bool lock_held; /* - * Select a victim buffer. The buffer is returned with its header + * Select a victim buffer. The buffer is returned with its header * spinlock still held! Also (in most cases) the BufFreelistLock is * still held, since it would be bad to hold the spinlock while * possibly waking up other processes. @@ -656,7 +656,7 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, * If using a nondefault strategy, and writing the buffer * would require a WAL flush, let the strategy decide whether * to go ahead and write/reuse the buffer or to choose another - * victim. We need lock to inspect the page LSN, so this + * victim. We need lock to inspect the page LSN, so this * can't be done inside StrategyGetBuffer. */ if (strategy != NULL) @@ -786,7 +786,7 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, { /* * We can only get here if (a) someone else is still reading - * in the page, or (b) a previous read attempt failed. We + * in the page, or (b) a previous read attempt failed. We * have to wait for any active read attempt to finish, and * then set up our own read attempt if the page is still not * BM_VALID. StartBufferIO does it all. @@ -879,7 +879,7 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum, * This is used only in contexts such as dropping a relation. We assume * that no other backend could possibly be interested in using the page, * so the only reason the buffer might be pinned is if someone else is - * trying to write it out. We have to let them finish before we can + * trying to write it out. We have to let them finish before we can * reclaim the buffer. * * The buffer could get reclaimed by someone else while we are waiting @@ -978,7 +978,7 @@ retry: * * Marks buffer contents as dirty (actual write happens later). * - * Buffer must be pinned and exclusive-locked. (If caller does not hold + * Buffer must be pinned and exclusive-locked. (If caller does not hold * exclusive lock, then somebody could be in process of writing the buffer, * leading to risk of bad data written to disk.) */ @@ -1027,7 +1027,7 @@ MarkBufferDirty(Buffer buffer) * * Formerly, this saved one cycle of acquiring/releasing the BufMgrLock * compared to calling the two routines separately. Now it's mainly just - * a convenience function. However, if the passed buffer is valid and + * a convenience function. However, if the passed buffer is valid and * already contains the desired block, we just return it as-is; and that * does save considerable work compared to a full release and reacquire. * @@ -1079,7 +1079,7 @@ ReleaseAndReadBuffer(Buffer buffer, * when we first pin it; for other strategies we just make sure the usage_count * isn't zero. (The idea of the latter is that we don't want synchronized * heap scans to inflate the count, but we need it to not be zero to discourage - * other backends from stealing buffers from our ring. As long as we cycle + * other backends from stealing buffers from our ring. As long as we cycle * through the ring faster than the global clock-sweep cycles, buffers in * our ring won't be chosen as victims for replacement by other backends.) * @@ -1087,7 +1087,7 @@ ReleaseAndReadBuffer(Buffer buffer, * * Note that ResourceOwnerEnlargeBuffers must have been done already. * - * Returns TRUE if buffer is BM_VALID, else FALSE. This provision allows + * Returns TRUE if buffer is BM_VALID, else FALSE. This provision allows * some callers to avoid an extra spinlock cycle. */ static bool @@ -1241,7 +1241,7 @@ BufferSync(int flags) * have the flag set. * * Note that if we fail to write some buffer, we may leave buffers with - * BM_CHECKPOINT_NEEDED still set. This is OK since any such buffer would + * BM_CHECKPOINT_NEEDED still set. This is OK since any such buffer would * certainly need to be written for the next checkpoint attempt, too. */ num_to_write = 0; @@ -1344,7 +1344,7 @@ BufferSync(int flags) * This is called periodically by the background writer process. * * Returns true if it's appropriate for the bgwriter process to go into - * low-power hibernation mode. (This happens if the strategy clock sweep + * low-power hibernation mode. (This happens if the strategy clock sweep * has been "lapped" and no buffer allocations have occurred recently, * or if the bgwriter has been effectively disabled by setting * bgwriter_lru_maxpages to 0.) @@ -2110,7 +2110,7 @@ BufferGetLSNAtomic(Buffer buffer) * specified relation fork that have block numbers >= firstDelBlock. * (In particular, with firstDelBlock = 0, all pages are removed.) * Dirty pages are simply dropped, without bothering to write them - * out first. Therefore, this is NOT rollback-able, and so should be + * out first. Therefore, this is NOT rollback-able, and so should be * used only with extreme caution! * * Currently, this is called only from smgr.c when the underlying file @@ -2119,7 +2119,7 @@ BufferGetLSNAtomic(Buffer buffer) * be deleted momentarily anyway, and there is no point in writing it. * It is the responsibility of higher-level code to ensure that the * deletion or truncation does not lose any data that could be needed - * later. It is also the responsibility of higher-level code to ensure + * later. It is also the responsibility of higher-level code to ensure * that no other process could be trying to load more pages of the * relation into buffers. * @@ -2281,9 +2281,9 @@ DropRelFileNodesAllBuffers(RelFileNodeBackend *rnodes, int nnodes) * * This function removes all the buffers in the buffer cache for a * particular database. Dirty pages are simply dropped, without - * bothering to write them out first. This is used when we destroy a + * bothering to write them out first. This is used when we destroy a * database, to avoid trying to flush data to disk when the directory - * tree no longer exists. Implementation is pretty similar to + * tree no longer exists. Implementation is pretty similar to * DropRelFileNodeBuffers() which is for destroying just one relation. * -------------------------------------------------------------------- */ |