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Deepvacuum twitter3/1/2023 I presume that the table is large enough so that the majority of it's pages must be read from disk (they are not present in Postgres shared memory), so the read_bytes field is good enough to be used as a progress counter.Įverytime I did this, the total bytes read by the process was no more than 5% from the total relation size, so I guess this approach may be good enough for You. I presume that the VACUUM must read through the whole table (including indexes and TOAST), whose disk size I know from the step 1. While it may take a bit more work it will essentially go through and download every single one - it takes a bit of tinkering to get the formatting down, but once you do it all works like a charm. This gives me rough idea on how many bytes are processed (read) every minute by the VACUUM. What deepvacuum will do for you is automatically download the links contained within a text file which you import into the program. ![]() ![]() In Linux shell I run while true do cat /proc/123/io | grep read_bytes sleep 60 done (where 123 is the pid) - this shows me bytes read by the process from the disk so far.I find the pid of the VACUUM process (in pg_catalog.pg_stat_activity).This gives me the idea of how many bytes the VACUUM has to read. I get table's disk size using pg_total_relation_size() - this includes indexes and TOAST size, which is what VACUUM processes.Save big in 2015 with 10 off your order Use Coupon Code 10OFF2015 at checkout. I'm not sure what query to run, because when I run VACUUM VERBOSE, I see that not only tables, but indexes on them are being processed too. Enjoy 10 during our President's Day Sale promotion - use coupon code PRES10OFF at checkout. Others are so fragile that they cannot withstand a deep vacuum and the air enclosed in. On the other hand, autovacuum_vacuum_threshold and autovacuum_vacuum_scale_factor settings alone prove that postgres itself knows something about the amount of change on the tables and probably puts it in the hands of the DBA too. Some materials are insufficient and crack after a few freezing cycles. So it is possible to have an estimation, even if it means one has to ANALYZE the table before. I've seen that pg_catalog.pg_stat_all_tables has a column for number of dead tuples. It is really annoying to have no clue when VACUUM will finish, whatsoever. Just a rough hint on the number of dead tuples or necessary I/O bytes is enough to decide. I've tried to use this technique on Postgres 9.5 to time-estimate my VACCUM ANALYSE VERBOSE bigtable, which has been running for 5.5 hours now.What I see in pgtotalrelationsize() is 718GB for bigtable, but while true do cat /proc/123/io grep readbytes sleep 60 on the VACCUM pid shows 2256301645824 bytes read so far (over 2TB). I'm not looking for a bullet-proof solution. Also if there were a progress indicator for postgres vacuum operations, it would be really helpful. I want to be able to roughly tell how much time a particular vacuum command will take, to be able to decide whether to cancel it or not. The question is sometimes autovacuum process on a table, takes a very long time (days) to complete. Some tables only receive large number of inserts and deletes, some other few inserts and large number of updates.ĭatabase runs on PostgreSQL 8.4 on a Debian 6.0 amd64 system with 16 gigabytes of RAM. I manage a big (some hundreds of gigs) database containing tables with various roles, some of them holding millions of records. sites, ftp catalogs, link lists from a text file, pictures, music, clips and more. ![]() Program includes a vast number of options to fine tune your downloads through. NASH Air Ejector Hybrid systems combine the low maintenance. Top Software Keywords Show more Show less Air Jets Combine with Liquid Ring Pumps to Deliver Deep Vacuum when Steam is Not Available.
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