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From: Paolo Bonzini <pbonzini@redhat.com>
To: John Snow <jsnow@redhat.com>, qemu-devel@nongnu.org
Cc: marc.mari.barcelo@gmail.com, afaerber@suse.de, stefanha@redhat.com
Subject: Re: [Qemu-devel] [PATCH v2 4/4] libqos/ahci: Swap memread/write with bufread/write
Date: Tue, 05 May 2015 12:35:44 +0200	[thread overview]
Message-ID: <55489D00.7050303@redhat.com> (raw)
In-Reply-To: <554416B2.50904@redhat.com>



On 02/05/2015 02:13, John Snow wrote:
>>
> 
> I wrote a loop to batch the ascii-hex conversion instead of letting
> printf do it; then ran some more very, very scientific tests:
> 
> memset alone:
> real    0m10.888s
> user    0m9.303s
> sys    0m9.146s
> 
> send-batching:
> real    0m6.541s
> user    0m5.027s
> sys    0m4.941s
> 
> memset+batching+b64:
> real    0m3.675s
> user    0m2.582s
> sys    0m1.718s
> 
> So it still seems as if the b64 batching is a strict improvement
> speed-wise. I'll send the non-b64 batching patch separately later,
> unless you have thoughts otherwise.

Ok, this is more similar to what I'd expect (3.6 * 6 / 4 = 5.4, I'm not
sure if you have the memset optimization in the send-batching test).

Hex is obviously more debuggable compared to Base64 (unless you starred
in the Matrix movies), so I'm a bit undecided about this one.  Anyone
can break the tie?

Paolo

  reply	other threads:[~2015-05-05 10:35 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-01 19:55 [Qemu-devel] [PATCH v2 0/4] qtest: base64 r/w and faster memset John Snow
2015-05-01 19:55 ` [Qemu-devel] [PATCH v2 1/4] qtest: allow arbitrarily long sends John Snow
2015-05-01 19:55 ` [Qemu-devel] [PATCH v2 2/4] qtest: Add base64 encoded read/write John Snow
2015-05-01 19:55 ` [Qemu-devel] [PATCH v2 3/4] qtest: add memset to qtest protocol John Snow
2015-05-01 19:55 ` [Qemu-devel] [PATCH v2 4/4] libqos/ahci: Swap memread/write with bufread/write John Snow
2015-05-01 20:48   ` Paolo Bonzini
2015-05-01 21:04     ` John Snow
2015-05-02  0:13     ` John Snow
2015-05-05 10:35       ` Paolo Bonzini [this message]
2015-05-05 15:48         ` John Snow
2015-05-05 16:19           ` Paolo Bonzini
2015-05-05 16:26             ` John Snow

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