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
next prev parent 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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