Re: [HACKERS] Everything leaks; How it mm suppose to work?

>
>
> >
> >Running postgresql in interactive mode shows that for each query I
> >type there is memory lost. The exact amount of memory lost depends on
> >the query I use. The amount of memory not freed is also a function
> >of the number of tuples returned.
> >
>
> Oops, it seems some palloc'ed memory is not freed by pfree() but
> using some other function(s).
> My mistake, sorry.

OK, I think I know where the leak is from. I checked AllocSetDump(), and
it did not show any problems with any context growing, so I started to
suspect direct calls to malloc(). I tried trapping on malloc(), but
there are too many calls.

Then I ran profiling on the two queries I mentioned, where one leaks and
one doesn't, and found that the leaking one had 500 extra calls to
malloc. Grep'ing out the calls and comparing the output of the two
profiles, I found:

0.00 0.00 1/527 ___irs_gen_acc [162]
0.00 0.00 35/527 _GetDatabasePath [284]
0.00 0.00 491/527 _GetDatabaseName [170]
[166] 0.8 0.00 0.00 527 _strdup [166]
0.00 0.00 527/2030 _malloc [105]
0.00 0.00 527/604 _strlen [508]
0.00 0.00 527/532 _bcopy [515]

I believe this code was modified by Vadim to fix our problem with blind
write errors when using psql while the regression tests were being run.

Am I correct on this? I have not developed a fix yet.

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