From: Mark Lord <liml@rtr.ca>
To: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>,
alan@lxorguk.ukuu.org.uk, linux-ide@vger.kernel.org
Subject: Re: Polling (was Re: [PATCHSET 2/2] implement PMP support, take 6)
Date: Fri, 28 Sep 2007 10:20:14 -0400 [thread overview]
Message-ID: <46FD0D9E.7040808@rtr.ca> (raw)
In-Reply-To: <46F9BF3E.5050708@garzik.org>
Jeff Garzik wrote:
..
> As such, polling is simply an outmoded concept. It does not make sense
> on new hardware, and forcing design decisions down that path only lead
> to a cascade of similar design decisions -- pmp_read polling being just
> one example of such a result.
A related tangent here, but I wonder if someday we might consider
something like NAPI for libata. Our I/O rates can far exceed those of the
network stack, and there polling (NAPI) has helped quite a bit.
But our data behaviour is mostly synchronous, whereas network stuff is more
asynchronous. But still, with multiple drives all using NCQ on a port,
a polled interface option might give higher throughput and lower CPU loading.
Just like with the networking code.
Not that this specifically relates to concerns with the current PMP patches,
but I'm curious where Jeff sees this all going, as he works on both sides.
Cheers
next prev parent reply other threads:[~2007-09-28 14:20 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-23 4:19 [PATCHSET 2/2] implement PMP support, take 6 Tejun Heo
2007-09-23 4:19 ` [PATCH 01/10] libata-pmp: update ata_eh_reset() for PMP Tejun Heo
2007-09-23 4:19 ` [PATCH 05/10] libata-pmp: implement qc_defer for command switching PMP support Tejun Heo
2007-09-23 4:19 ` [PATCH 08/10] ahci: implement " Tejun Heo
2007-09-23 4:19 ` [PATCH 03/10] libata-pmp: hook PMP support and enable it Tejun Heo
2007-09-23 4:19 ` [PATCH 04/10] libata-pmp: extend ACPI support to cover PMP Tejun Heo
2007-09-23 4:19 ` [PATCH 06/10] sata_sil24: implement PMP support Tejun Heo
2007-09-23 4:19 ` [PATCH 07/10] sata_sil24: implement PORT_RST Tejun Heo
2007-09-23 4:19 ` [PATCH 02/10] libata-pmp: implement Port Multiplier support Tejun Heo
2007-09-23 4:19 ` [PATCH 09/10] ahci: move host flags over to pi.private_data Tejun Heo
2007-09-23 4:19 ` [PATCH 10/10] ahci: implement AHCI_HFLAG_NO_PMP Tejun Heo
2007-09-26 2:09 ` Polling (was Re: [PATCHSET 2/2] implement PMP support, take 6) Jeff Garzik
2007-09-26 2:12 ` Jeff Garzik
2007-09-26 8:41 ` Tejun Heo
2007-09-28 12:10 ` Tejun Heo
2007-09-28 13:54 ` Jeff Garzik
2007-09-28 14:18 ` Tejun Heo
2007-09-28 14:57 ` Alan Cox
2007-09-28 15:20 ` Jeff Garzik
2007-09-28 15:43 ` Alan Cox
2007-09-28 15:40 ` Jeff Garzik
2007-09-28 20:00 ` Mark Lord
2007-09-29 1:49 ` Jeff Garzik
2007-09-29 3:29 ` Jeff Garzik
2007-09-29 4:58 ` Andrew Morton
2007-09-29 5:09 ` Jeff Garzik
2007-09-29 16:51 ` Greg Freemyer
2007-09-29 20:56 ` Alan Cox
2007-10-01 12:28 ` Jeff Garzik
2007-09-28 15:22 ` Jeff Garzik
2007-09-28 16:48 ` Tejun Heo
2007-09-28 20:02 ` Mark Lord
2007-09-28 20:25 ` Bartlomiej Zolnierkiewicz
2007-09-28 21:03 ` Alan Cox
2007-09-29 1:43 ` Jeff Garzik
2007-09-29 5:24 ` Tejun Heo
2007-10-01 13:31 ` Jeff Garzik
2007-10-02 0:11 ` Tejun Heo
2007-10-02 14:25 ` Alan Cox
2007-10-02 14:30 ` Jeff Garzik
2007-09-29 12:32 ` Mark Lord
2007-10-01 12:38 ` Jeff Garzik
2007-10-02 0:12 ` Tejun Heo
2007-10-02 12:56 ` Jeff Garzik
2007-10-02 13:06 ` Mark Lord
2007-10-02 13:30 ` Jeff Garzik
2007-10-06 22:02 ` Tejun Heo
2007-10-09 2:09 ` Jeff Garzik
2007-10-09 6:54 ` Tejun Heo
2007-09-28 14:20 ` Mark Lord [this message]
2007-09-28 15:36 ` Jeff Garzik
2007-09-28 15:55 ` Alan Cox
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