On Wed, Dec 11, 2019 at 09:15:07PM +0900, Michael Paquier wrote: > On Fri, Dec 06, 2019 at 10:23:25AM -0600, Justin Pryzby wrote: > > Find attached updated patch: > > . Use structure to include relation name. > > . Split into a separate patch rename of "StringInfoData buf". > > > > 2019-11-27 20:04:53.640 CST [14244] ERROR: canceling statement due to > > statement timeout > > 2019-11-27 20:04:53.640 CST [14244] CONTEXT: block 2314 of relation t > > 2019-11-27 20:04:53.640 CST [14244] STATEMENT: vacuum t; > > > > I tried to use BufferGetTag() to avoid using a 2ndary structure, but fails > > if > > the buffer is not pinned. > > No problem from me to add more context directly in lazy_scan_heap().
Do you mean without a callback ? I think that's necessary, since the IO errors would happen within ReadBufferExtended, but we don't want to polute that with errcontext. And cannot call errcontext on its own: FATAL: errstart was not called > So I would suggest the following instead: > "while scanning block %u of relation \"%s.%s\"" Done in the attached.
>From b78505f3008b501b1d427c491bc0f8b796d68879 Mon Sep 17 00:00:00 2001 From: Justin Pryzby <pryz...@telsasoft.com> Date: Wed, 20 Nov 2019 14:53:20 -0600 Subject: [PATCH v3] vacuum errcontext to show block being processed As requested here. https://www.postgresql.org/message-id/20190807235154.erbmr4o4bo6vgnjv%40alap3.anarazel.de --- src/backend/access/heap/vacuumlazy.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index 043ebb4..9376989 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -138,6 +138,12 @@ typedef struct LVRelStats bool lock_waiter_detected; } LVRelStats; +typedef struct +{ + char *relname; + char *relnamespace; + BlockNumber blkno; +} vacuum_error_callback_arg; /* A few variables that don't seem worth passing around as parameters */ static int elevel = -1; @@ -175,6 +181,7 @@ static bool lazy_tid_reaped(ItemPointer itemptr, void *state); static int vac_cmp_itemptr(const void *left, const void *right); static bool heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cutoff_xid, bool *all_frozen); +static void vacuum_error_callback(void *arg); /* @@ -524,6 +531,8 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, PROGRESS_VACUUM_MAX_DEAD_TUPLES }; int64 initprog_val[3]; + ErrorContextCallback errcallback; + vacuum_error_callback_arg cbarg; pg_rusage_init(&ru0); @@ -635,6 +644,15 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, else skipping_blocks = false; + /* Setup error traceback support for ereport() */ + errcallback.callback = vacuum_error_callback; + cbarg.relname = relname; + cbarg.relnamespace = get_namespace_name(RelationGetNamespace(onerel)); + cbarg.blkno = 0; /* Not known yet */ + errcallback.arg = (void *) &cbarg; + errcallback.previous = error_context_stack; + error_context_stack = &errcallback; + for (blkno = 0; blkno < nblocks; blkno++) { Buffer buf; @@ -658,6 +676,8 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_SCANNED, blkno); + cbarg.blkno = blkno; + if (blkno == next_unskippable_block) { /* Time to advance next_unskippable_block */ @@ -817,7 +837,6 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, buf = ReadBufferExtended(onerel, MAIN_FORKNUM, blkno, RBM_NORMAL, vac_strategy); - /* We need buffer cleanup lock so that we can prune HOT chains. */ if (!ConditionalLockBufferForCleanup(buf)) { @@ -1388,6 +1407,9 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, RecordPageWithFreeSpace(onerel, blkno, freespace); } + /* Pop the error context stack */ + error_context_stack = errcallback.previous; + /* report that everything is scanned and vacuumed */ pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_SCANNED, blkno); @@ -2354,3 +2376,15 @@ heap_page_is_all_visible(Relation rel, Buffer buf, return all_visible; } + +/* + * Error context callback for errors occurring during vacuum. + */ +static void +vacuum_error_callback(void *arg) +{ + vacuum_error_callback_arg *cbarg = arg; + + errcontext("while scanning block %u of relation \"%s.%s\"", + cbarg->blkno, cbarg->relnamespace, cbarg->relname); +} -- 2.7.4
