On 2016-10-15 17:43:40 -0700, Jeff Janes wrote: > On Fri, Oct 14, 2016 at 11:51 AM, Andres Freund <and...@anarazel.de> wrote: > > > On 2016-10-14 13:11:51 +0200, Christoph Berg wrote: > > > Re: Michael Paquier 2016-02-10 <CAB7nPqS=wBbZzBcty1KyN- > > 5y9bpxz+dejbfcctebf06ef2u...@mail.gmail.com> > > > > On Mon, Feb 8, 2016 at 11:32 PM, Andres Freund <and...@anarazel.de> > > wrote: > > > > > Frequently when reading postgres logs to do some post mortem analysis > > > > > I'm left wondering what process emitted an error/log message. After > > the > > > > > fact it's often hard to know wether an error message was emitted by a > > > > > user backend or by something internal, say the checkpointer or > > > > > autovacuum. Logging all process starts is often impractical given > > the > > > > > log volume that causes. > > > > > > > > > > So I'm proposing adding an escape displaying the process title (say > > 'k' > > > > > for kind?). So %k would emit something like "autovacuum worker > > process", > > > > > "wal sender process" etc. > > > > > > > > It would be nice to get something consistent between the ps output and > > > > this new prefix, say with for example a miscadmin.h parameter like > > > > MyProcName. > > > > > > > > > I'm thinking it might make sense to give normal connections "" as the > > > > > name, they're usually already discernible. > > > > > > > > Yeah, that sounds fine for me. What about background workers? I would > > > > think that they should use BackgroundWorker->bgw_name. > > > > > > (Rediscovering an old horse) > > > > > > Couldn't these processes just set %a = application_name? > > > > It'd not get me what I'd want, no. E.g for walsenders that'd not be > > parsable in a meaningful way. I really would like an escape that'd > > always output one of: > > Postmaster, Startup, BgWriter, Checkpointer, WalWriter, WalReceiver, > > AutovacLauncher, AutovacWorker, PgArch, PgStat, SysLogger, Backend, > > BackgroundWorker. > > > > I'm not sure what you are proposing. Which of those 13 strings you listed > would a walsender advertise itself as?
Oops, left that one out (as it's not one of the pids explicitly listed in postmaster.c, which I went over). 'WalSender'. > Why would stuffing one of those words into %k be different than > stuffing that same word into %a, where %a would otherwise be the empty > string? Because you very well might want to keep tracking application_name for walsenders - as that's important e.g. for sync replica tracking purposes - and be able to categorize log messages by the type of process. - Andres -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers