On 09/07/2016 01:13 PM, Amit Kapila wrote: > On Wed, Sep 7, 2016 at 1:08 AM, Tomas Vondra > <tomas.von...@2ndquadrant.com> wrote: >> On 09/06/2016 04:49 AM, Amit Kapila wrote: >>> On Mon, Sep 5, 2016 at 11:34 PM, Tomas Vondra >>> <tomas.von...@2ndquadrant.com> wrote: >>>> >>>> >>>> On 09/05/2016 06:03 AM, Amit Kapila wrote: >>>>> So, in short we have to compare three >>>>> approaches here. >>>>> >>>>> 1) Group mode to reduce CLOGControlLock contention >>>>> 2) Use granular locking model >>>>> 3) Use atomic operations >>>>> >>>>> For approach-1, you can use patch [1]. For approach-2, you can use >>>>> 0001-Improve-64bit-atomics-support patch[2] and the patch attached >>>>> with this mail. For approach-3, you can use >>>>> 0001-Improve-64bit-atomics-support patch[2] and the patch attached >>>>> with this mail by commenting USE_CONTENT_LOCK. If the third doesn't >>>>> work for you then for now we can compare approach-1 and approach-2. >>>>> >>>> >>>> OK, I can compile all three cases - but onl with gcc 4.7 or newer. Sadly >>>> the 4-socket 64-core machine runs Debian Jessie with just gcc 4.6 and my >>>> attempts to update to a newer version were unsuccessful so far. >>>> >>> >>> So which all patches your are able to compile on 4-socket m/c? I >>> think it is better to measure the performance on bigger machine. >> >> Oh, sorry - I forgot to mention that only the last test (with >> USE_CONTENT_LOCK commented out) fails to compile, because the functions >> for atomics were added in gcc-4.7. >> > > No issues, in that case we can leave the last test for now and do it later. >
FWIW I've managed to compile a new GCC on the system (all I had to do was to actually read the damn manual), so I'm ready to do the test once I get a bit of time. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers