From: "Taku Izumi" <izumi2005@soft.fujitsu.com>
To: "Russell King" <rmk@arm.linux.org.uk>
Cc: akpm@osdl.org, mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: performance-improvement-of-serial-console-via-virtual.patch added to -mm tree
Date: Thu, 8 Sep 2005 16:47:32 +0900 (JST) [thread overview]
Message-ID: <4394.10.124.102.246.1126165652.squirrel@dominion> (raw)
In-Reply-To: <20050907224911.H19199@flint.arm.linux.org.uk>
Dear Russell:
>I don't think we want this. With early serial console, tx_loadsz is
>not guaranteed to be initialised, and may in fact be zero.
>Plus there's no guarantee that the FIFOs will actually be enabled, so
>I think it's better that this patch doesn't go to mainline.
Our server has a virtual serial port, but its performance seems to be poor.
It takes 10 seconds to output 4000 characters (from kernel) to serial
console. By applying my patch, its peformance could be improved. ( 0.4
seconds / 4000 characters output), so I think it is useful to use FIFO at
serial8250_console_write function like transmit_chars function. Where
should I correct in order to use FIFO?
Taku Izumi <izumi2005@soft.fujitsu.com>
next parent reply other threads:[~2005-09-08 7:47 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <200509072146.j87LkNv8004076@shell0.pdx.osdl.net>
[not found] ` <20050907224911.H19199@flint.arm.linux.org.uk>
2005-09-08 7:47 ` Taku Izumi [this message]
2005-09-13 8:17 ` Russell King
2005-09-13 11:44 ` Hironobu Ishii
2005-09-13 11:53 ` Russell King
2005-09-13 12:02 ` Russell King
2005-09-13 13:07 ` Hironobu Ishii
2005-09-15 5:20 ` Taku Izumi
2005-09-13 12:18 ` Hironobu Ishii
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