diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/access/transam/xlogreader.c | 17 | ||||
| -rw-r--r-- | src/include/access/heapam_xlog.h | 8 |
2 files changed, 17 insertions, 8 deletions
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index 0973d778ac9..db8f3a34e21 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -1248,7 +1248,22 @@ DecodeXLogRecord(XLogReaderState *state, XLogRecord *record, char **errormsg) { if (state->main_data) pfree(state->main_data); - state->main_data_bufsz = state->main_data_len; + + /* + * main_data_bufsz must be MAXALIGN'ed. In many xlog record + * types, we omit trailing struct padding on-disk to save a few + * bytes; but compilers may generate accesses to the xlog struct + * that assume that padding bytes are present. If the palloc + * request is not large enough to include such padding bytes then + * we'll get valgrind complaints due to otherwise-harmless fetches + * of the padding bytes. + * + * In addition, force the initial request to be reasonably large + * so that we don't waste time with lots of trips through this + * stanza. BLCKSZ / 2 seems like a good compromise choice. + */ + state->main_data_bufsz = MAXALIGN(Max(state->main_data_len, + BLCKSZ / 2)); state->main_data = palloc(state->main_data_bufsz); } memcpy(state->main_data, ptr, state->main_data_len); diff --git a/src/include/access/heapam_xlog.h b/src/include/access/heapam_xlog.h index caa0f14f4bf..2a3ce355d99 100644 --- a/src/include/access/heapam_xlog.h +++ b/src/include/access/heapam_xlog.h @@ -333,13 +333,7 @@ typedef struct xl_heap_new_cid TransactionId top_xid; CommandId cmin; CommandId cmax; - - /* - * don't really need the combocid since we have the actual values right in - * this struct, but the padding makes it free and its useful for - * debugging. - */ - CommandId combocid; + CommandId combocid; /* just for debugging */ /* * Store the relfilenode/ctid pair to facilitate lookups. |