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From: Kasper Janssens <Kasper.Janssens@hgst.com>
To: "caml-list@inria.fr" <caml-list@inria.fr>
Subject: [Caml-list] Profiling ocaml with lwt
Date: Wed, 9 Mar 2016 08:54:30 +0000	[thread overview]
Message-ID: <1CF03778-3645-47D9-A713-4341373801F3@HGST.com> (raw)

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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  8:54 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-09  8:54 Kasper Janssens [this message]
2016-03-09  9:49 ` Malcolm Matalka
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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