Prefetch blocks during lazy vacuum's truncation scan Vacuum truncation scan can be sped up on rotating media by prefetching blocks in forward direction. That makes the blocks already present in memory by the time they are needed, while also letting OS read-ahead kick in.
The truncate scan has been measured to be five times faster than without this patch (that was on a slow disk, but it shouldn't hurt on fast disks.) Author: Álvaro Herrera, loosely based on a submission by Claudio Freire Discussion: https://postgr.es/m/cagtbqpa6nfgo_6g_y_7zqx8l9gchdsqkydo1tguh791z6py...@mail.gmail.com Branch ------ master Details ------- http://git.postgresql.org/pg/commitdiff/7e26e02eec90370dd222f35f00042f8188488ac4 Modified Files -------------- src/backend/commands/vacuumlazy.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) -- Sent via pgsql-committers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
