On Wed, Jun 14, 2017 at 6:28 PM, Justin Pryzby <pry...@telsasoft.com> wrote: > On Tue, Jun 13, 2017 at 12:16:00PM -0400, Robert Haas wrote: >> It might be worth adding platform-specific code for common platforms. > > All I care (which linux happily/happens to support) is maxrss; I was probably > originally interested in this while digging into an issue with hash agg. > > I think it's fine to show zeros for unsupported fields; that's what > getusage(2) > and time(1) do after all.
Meh. I think if we're going to go to the trouble of customizing this code by platform, we ought to get rid of values that are meaningless on that platform. >> it would be a good idea to install code specific to Linux that >> displays all and only those values that are meaningful on Linux, and >> (less importantly) similarly for macOS. Linux is such a common >> platform that reporting bogus zero values and omitting other fields >> that are actually meaningful does not seem like a very good plan. > > That has the issue that it varies not just by OS but also by OS version. For > example PG already shows context switches and FS in/out puts, but they're > nonzero only since linux 2.6 (yes, 2.4 is ancient and unsupported but still). > > ru_nvcsw (since Linux 2.6) > ru_inblock (since Linux 2.6.22) If people who are still running 10 or 15 year old versions of Linux see some zeroes for fields that might've been populated on a newer release, I'm OK with that. Maybe it will encourage them to upgrade. We've completely removed platform support for systems newer than that. > ..and other fields are "currently unused", but maybe supported in the past or > future(?) > ru_ixrss (unmaintained) > This field is currently unused on Linux. Could be worth a bit of research here. > Are you thinking of something like this, maybe hidden away in a separate file > somewhere? > > #if defined(__linux__) || defined(BSD) > appendStringInfo(&str, "!\t%ld max resident, %ld shared, %ld unshared > data, %ld unshared stack (kB)\n", r.ru_maxrss, r.ru_ixrss, r.ru_idrss, > r.ru_isrss); > #elif defined(__darwin__) > appendStringInfo(&str, "!\t%ld max resident, %ld shared, %ld unshared > data, %ld unshared stack (kB)\n", r.ru_maxrss/1024, r.ru_ixrss/1024, > r.ru_idrss/1024, r.ru_isrss/1024); > #endif /* __linux__ */ I don't think it needs to go in a separate file. I'd just patch ShowUsage(). -- 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
