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From: Malcolm Matalka <mmatalka@gmail.com>
To: Kasper Janssens <Kasper.Janssens@hgst.com>
Cc: caml-list <caml-list@inria.fr>
Subject: Re: [Caml-list] Profiling ocaml with lwt
Date: Wed, 9 Mar 2016 10:49:04 +0100	[thread overview]
Message-ID: <CAKziXDXhpg5ftsGXe5gg1xfHXRrr6cMdkWLDjy9sFqNYJ6BNZA@mail.gmail.com> (raw)
In-Reply-To: <1CF03778-3645-47D9-A713-4341373801F3@HGST.com>

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Generally I wrap external calls in something that gets that gets the wall
time of an external service call and logs it somewhere.
Den 9 mar 2016 9:54 fm skrev "Kasper Janssens" <Kasper.Janssens@hgst.com>:

> Hello,
>
>
> I’m trying to profile an ocaml application that has a performance
> degradation of about 20 %, with quite some code changes between both
> versions. I tried attaching perf and gprof to it, but to no real avail.
> Sure, there are slight differences in the running time of functions in the
> gprof result, but nothing whatsoever that seems to explain that kind of
> delay. Perf doesn’t seem to indicate a problem neither.
>
>
> The thing is, I think it’s a delay in one of the servers that the
> application communicates with. The communication to those servers is done
> asynchronously, through lwt (epoll). I suspect that is the reason why
> delays in that communication don’t show up in the gprof result, but I’m not
> really sure.
>
>
> Does anybody know of a way to profile lwt applications in a way that these
> kinds of delays might show up so I know which backend system I have to
> focus on?
>
>
> Kasper
>
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  reply	other threads:[~2016-03-09  9:49 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-09  8:54 Kasper Janssens
2016-03-09  9:49 ` Malcolm Matalka [this message]
2016-03-09  9:57   ` Kasper Janssens
2016-03-10  7:41     ` Török Edwin
2016-03-10  7:55       ` Malcolm Matalka
2016-03-09 18:13 ` Adrien Nader
     [not found] <1911376179.6660816.1457526862329.JavaMail.yahoo.ref@mail.yahoo.com>
2016-03-09 12:34 ` tools

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