Re: HAProxy Response time performance

Hello Matt,

You need to activate logging to see what occurs to your requests, you can use "halog" tool (in the contrib folder) to filter out fast requests.

Other things you can enable to reduce latency is : option tcp-smart-accept
option tcp-smart-connect

and finally you can test :
option splice-response
But this one will be dependent of your kind of traffic.

next release 1.4.16 have some improvements in latency (http://www.mail-archive.com/haproxy@formilux.org/msg05080.html), i think you can give it a try, take the daily snapshot for this.

Regards,

Hervé.

On Wed, 8 Jun 2011 23:57:38 -0700
Matt Christiansen <admin#nikore.net> wrote:

> Hello,
>
> I am wanting to move to HAProxy for my load balancing solution. Over
> all I have been greatly impressed with it. It has way more throughput
> and can handle way more connections then our current LB Solution
> (nginx). I have been noticing one issue in all of our tests though, it
> seems like in the TP99.9 (and greater) of response times is much MUCH
> higher then nginx and we have a lot of outliers.
>
> Our test makes a call to the VIP and times the time it takes to
> receive the data back then pauses for a sec or two and makes the next
> response. In both of the sample results below I did 2000 requests.
>
> HAProxy
>
> Average: 39.71128451818
> Median: 29.4217891182
> tp90: 67.48199012481
> tp99: 313.29083442688
> tp99.9: 562.318801879883
> Over 500ms: 10
> Over 2000ms: 0
>
> nginx
>
> Average: 69.6072148084641
> Median: 59.2541694641113
> tp90: 87.6350402832031
> tp99: 112.42142221222
> tp99.9: 180.88918274272
> Over 500ms: 0
> Over 2000ms: 0
>
> So as you can see a big difference in the TP99.9 and a big difference
> in the outlier count but the average and median response time are
> really low.
>
> We are running a pretty stock centos 5.6 server install with HAProxy
> 1.4.15, HAProxy isn't using more then like 4% of the CPU and the
> System CPU is closer to 12%.
>
> I was wondering if you guys had any obvious response time related
> performance tweaks I can try. If you need more info let me know too.
>
> Thanks,
> Matt C.
>

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