|From:||Anastasia Lubennikova <a(dot)lubennikova(at)postgrespro(dot)ru>|
|To:||Dirk Rudolph <dirk(dot)rudolph(at)netcentric(dot)biz>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>|
|Subject:||Re: Leaking memory in text_overlay function|
|Views:||Raw Message | Whole Thread | Download mbox | Resend email|
I found this thread on the open CF. As I see, the discussion is ended
with decision to reject patch.
I've just changed the status to "Rejected".
02.07.2016 18:11, Dirk Rudolph:
> Well that's good to know. It was just curious that, in my case, I only
> saw this in this particular function.
> Anyway. I will consider to handle the memory the same way, if this is
> the recommendation.
> Many thanks.
> On Sat, Jul 2, 2016 at 4:45 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us
> <mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us>> wrote:
> Dirk Rudolph <dirk(dot)rudolph(at)netcentric(dot)biz
> <mailto:dirk(dot)rudolph(at)netcentric(dot)biz>> writes:
> > while implementing my own C function, I mentioned that some
> memory is not freed by the text_overlay function in varlena.c
> By and large, that's intentional. SQL-called functions normally run
> in short-lived memory contexts, so that any memory they don't
> bother to
> pfree will be cleaned up automatically at the end of the tuple cycle.
> If we did not follow that approach, there would need to be many
> more explicit pfree calls than there are today, and the system
> would be
> net slower overall because multiple retail pfree's are slower than a
> There are places where it's important to avoid leaking memory,
> But I don't think this is one of them, unless you can demonstrate a
> scenario with query-lifespan or worse leakage.
> > Particularly I mean the both substrings allocated by
> text_substring (according to the documentation of text_substring
> "The result is always a freshly palloc'd datum.") and one of the
> concatenation results. I’m aware of the MemoryContext being
> deleted in my case but IMHO builtin functions should be memory safe.
> That is not the project policy.
> regards, tom lane
> Dirk Rudolph | Senior Software Engineer
> Netcentric AG
> M: +41 79 642 37 11
> D: +49 174 966 84 34
> dirk(dot)rudolph(at)netcentric(dot)biz <mailto:dirk(dot)rudolph(at)netcentric(dot)biz> |
> www.netcentric.biz <http://www.netcentric.biz/>
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company
|Next Message||Torsten Zuehlsdorff||2016-08-04 09:00:25||Re: Why we lost Uber as a user|
|Previous Message||Andres Freund||2016-08-04 07:52:46||Re: [RFC] Change the default of update_process_title to off|