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Date: Fri, 20 Dec 2019 10:48:47 +0300
From: Konstantin Osipov <kostja.osipov@gmail.com>
Message-ID: <20191220074847.GF30445@atlas>
References: <20191217125420.20881-1-gorcunov@gmail.com>
 <20191217125420.20881-2-gorcunov@gmail.com>
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In-Reply-To: <20191217125420.20881-2-gorcunov@gmail.com>
Subject: Re: [Tarantool-patches] [PATCH v6 1/4] coio: Export helpers and
 provide coio_read_fd_timeout
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To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: tml <tarantool-patches@dev.tarantool.org>

* Cyrill Gorcunov <gorcunov@gmail.com> [19/12/17 15:57]:
> There is no reason to hide functions. In particular
> we will use coio_write_fd_timeout and coio_read_fd_timeout
> for popen.

AFAIU the only difference between the new function and
coio_read_timeout() is that the new function works without 
struct coio* object, but uses coio_wait(), which creates/
destroys this object on demand.

Could you provide a rationale for this? coio_wait has to call 
EPOLL_CTL_ADD/EPOLL_CTL_DEL on every wait, so it tripples the 
number of syscalls per wait. 

On the other hand I realize that it's not super important
for popen IO, but still I don't understand *why* you need this.


-- 
Konstantin Osipov, Moscow, Russia