Re: [HACKERS] Comment in src/backend/commands/vacuumlazy.c
On Mon, Mar 24, 2014 at 12:28 AM, Amit Langote amitlangot...@gmail.com wrote: Hi, Note the following comment in src/backend/commands/vacuumlazy.c:lazy_scan_heap() 1088 /* If no indexes, make log report that lazy_vacuum_heap would've made */ 1089 if (vacuumed_pages) 1090 ereport(elevel, Just wondering if it would read better as: 1088 /* Make the log report that lazy_vacuum_heap would've made had there been no indexes */ Is that correct? No. Your rewrite means the opposite of what the comment means now. vacuumed_pages will be non-zero only if the relation does NOT have indexes. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] Comment in src/backend/commands/vacuumlazy.c
On Mon, Mar 31, 2014 at 11:44 PM, Robert Haas robertmh...@gmail.com wrote:
On Mon, Mar 24, 2014 at 12:28 AM, Amit Langote amitlangot...@gmail.com
wrote:
Hi,
Note the following comment in
src/backend/commands/vacuumlazy.c:lazy_scan_heap()
1088 /* If no indexes, make log report that lazy_vacuum_heap
would've made */
1089 if (vacuumed_pages)
1090 ereport(elevel,
Just wondering if it would read better as:
1088 /* Make the log report that lazy_vacuum_heap would've made
had there been no indexes */
Is that correct?
No. Your rewrite means the opposite of what the comment means now.
vacuumed_pages will be non-zero only if the relation does NOT have
indexes.
You are correct. It does sound opposite of what is actually happening:
Somewhere in c:lazy_scan_heap(),
941 /*
942 * If there are no indexes then we can vacuum the page right now
943 * instead of doing a second scan.
944 */
945 if (nindexes == 0
946 vacrelstats-num_dead_tuples 0)
947 {
948 /* Remove tuples from heap */
949 lazy_vacuum_page(onerel, blkno, buf, 0, vacrelstats, vmbuffer);
950 has_dead_tuples = false;
951
952 /*
953 * Forget the now-vacuumed tuples, and press on, but be careful
954 * not to reset latestRemovedXid since we want that value to be
955 * valid.
956 */
957 vacrelstats-num_dead_tuples = 0;
958 vacuumed_pages++;
959 }
Sorry about the noise.
--
Amit
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[HACKERS] Comment in src/backend/commands/vacuumlazy.c
Hi, Note the following comment in src/backend/commands/vacuumlazy.c:lazy_scan_heap() 1088 /* If no indexes, make log report that lazy_vacuum_heap would've made */ 1089 if (vacuumed_pages) 1090 ereport(elevel, Just wondering if it would read better as: 1088 /* Make the log report that lazy_vacuum_heap would've made had there been no indexes */ Is that correct? -- Amit -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
