Re: pg_upgrade and log file output on Windows

I have fixed the bug below with the attached patches for 9.0, 9.1, and
9.2. I did a minimal patch for 9.0 and 9.1, and a more thorough patch
for 9.2.

The use of -l/log was tested originally in pg_migrator (for 8.4) and
reported to be working, but it turns out it only worked in 'check' mode,
and threw an error during actual upgrade. This bug was reported to me
recently by EnterpriseDB testing of PG 9.0 on Windows. The 9.2 C
comments should make it clear that Windows doesn't allow multiple
processes to write to the same file and should avoid future breakage.

---------------------------------------------------------------------------

Bruce Momjian wrote:
> Has anyone successfully used pg_upgrade 9.0 with -l (log) on Windows?
>
> I received a private email bug report that pg_upgrade 9.0 does not work
> with the -l/log option on Windows. The error is:
>
> Analyzing all rows in the new cluster
> ""c:/MinGW/msys/1.0/home/edb/inst/bin/vacuumdb" --port 55445 --username "edb" --all --analyze
> >> c:/MinGW/msys/1.0/home/edb/auxschedule/test.log 2>&1"
> The process cannot access the file because it is being used by another
> process.
>
> What has me confused is this same code exists in pg_migrator, which was
> fixed to work with -l on Windows by Hiroshi Saito with this change:
>
> /*
> * On Win32, we can't send both server output and pg_ctl output
> * to the same file because we get the error:
> * "The process cannot access the file because it is being used by another process."
> * so we have to send pg_ctl output to 'nul'.
> */
> sprintf(cmd, SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" "
> "-o \"-p %d -c autovacuum=off -c autovacuum_freeze_max_age=2000000000\" "
> "start >> \"%s\" 2>&1" SYSTEMQUOTE,
> bindir, ctx->logfile, datadir, port,
> #ifndef WIN32
> ctx->logfile);
> #else
> DEVNULL);
> #endif
>
> The fix was not to use the same log file and output file for pg_ctl.
> But as you can see, the pg_ctl and vacuumdb code is unchanged:
>
> prep_status(ctx, "Analyzing all rows in the new cluster");
> exec_prog(ctx, true,
> SYSTEMQUOTE "\"%s/vacuumdb\" --port %d --username \"%s\" "
> "--all --analyze >> %s 2>&1" SYSTEMQUOTE,
> ctx->new.bindir, ctx->new.port, ctx->user, ctx->logfile);
>
> I can't figure out of there is something odd about this user's setup or
> if there is a bug in pg_upgrade with -l on Windows.
>
> --
> Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
> EnterpriseDB http://enterprisedb.com
>
> + It's impossible for everything to be true. +
>
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--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +