representation because the existing values have changed.

</para>

<para>

When autosummarization is enabled, each time a page range is filled a

request is sent to autovacuum for it to execute a targeted summarization

for that range, to be fulfilled at the end of the next worker run on the

same database. If the request queue is full, the request is not recorded

and a message is sent to the server log:

<screen>

LOG: request for BRIN range summarization for index "brin_wi_idx" page 128 was not recorded

</screen>

When this happens, the range will be summarized normally during the next

regular vacuum of the table.

</para>

</sect2>

</sect1>

brinGetTupleForHeapBlock(revmap,lastPageRange,&buf,&off,

NULL,BUFFER_LOCK_SHARE,NULL);

if (!lastPageTuple)

AutoVacuumRequestWork(AVW_BRINSummarizeRange,

RelationGetRelid(idxRel),

lastPageRange);

{

boolrecorded;

recorded=AutoVacuumRequestWork(AVW_BRINSummarizeRange,

RelationGetRelid(idxRel),

lastPageRange);

if (!recorded)

ereport(LOG,

(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),

errmsg("request for BRIN range summarization for index \"%s\" page %u was not recorded",

RelationGetRelationName(idxRel),

lastPageRange)));

}

LockBuffer(buf,BUFFER_LOCK_UNLOCK);

}

AutoVacuumRequestWork(AutoVacuumWorkItemTypetype,OidrelationId,

BlockNumberblkno)

{

inti;

boolresult= false;

LWLockAcquire(AutovacuumLock,LW_EXCLUSIVE);

workitem->avw_database=MyDatabaseId;

workitem->avw_relation=relationId;

workitem->avw_blockNumber=blkno;

result= true;

break;

}

LWLockRelease(AutovacuumLock);

returnresult;

}

externvoidAutovacuumLauncherIAm(void);

externvoidAutoVacuumRequestWork(AutoVacuumWorkItemTypetype,

externboolAutoVacuumRequestWork(AutoVacuumWorkItemTypetype,

OidrelationId,BlockNumberblkno);