From: William Lee Irwin III <wli@holomorphy.com>
To: Russell King <rmk@arm.linux.org.uk>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Serial: updated serial drivers
Date: Mon, 15 Jul 2002 03:03:10 -0700 [thread overview]
Message-ID: <20020715100310.GF23693@holomorphy.com> (raw)
In-Reply-To: <20020707010009.C5242@flint.arm.linux.org.uk>
On Sun, Jul 07, 2002 at 01:00:09AM +0100, Russell King wrote:
> I've been maintaining a serial driver "off the side" of the ARM port
> which cleans up the serial driver mess that we currently have, with
> many duplications of serial.c, each with subtle bugs.
global_cli() overhead on my testbox is a significant problem.
Profile info from tbench 1024 with ttyS0 as stdout, taken on a 16 cpu
i386 box with 16GB of RAM and irqbalance disabled, (needed to boot):
90372662 total 713.6412
44801051 default_idle 861558.6731
36220921 mod_timer 113190.3781
2510075 timer_bh 2764.3998
2344795 __global_cli 8620.5699
1446315 __wake_up 7693.1649
1370742 do_gettimeofday 10078.9853
924996 schedule 831.8309
512368 do_softirq 2328.9455
103136 tasklet_hi_action 526.2041
40640 system_call 923.6364
19238 do_page_fault 14.2927
12835 add_wait_queue 103.5081
10667 remove_wait_queue 83.3359
7990 bh_action 38.4135
5303 pte_alloc_one 27.6198
4665 schedule_timeout 29.1562
4584 pgd_alloc 24.3830
3870 syscall_call 351.8182
3633 try_to_wake_up 6.3073
3100 exit_notify 3.5068
2566 del_timer 14.9186
The disabling of irqbalance should make these profiling results valid.
Cheers,
Bill
next prev parent reply other threads:[~2002-07-15 10:01 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-07-07 0:00 Serial: updated serial drivers Russell King
2002-07-07 10:01 ` Miquel van Smoorenburg
2002-07-15 10:03 ` William Lee Irwin III [this message]
2002-07-15 11:01 ` William Lee Irwin III
2002-07-15 11:24 ` Russell King
2002-07-15 18:17 ` William Lee Irwin III
2002-07-15 14:25 ` Dave Hansen
-- strict thread matches above, loose matches on Subject: below --
2002-07-07 14:15 Marko Kohtala
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