Re: [9fans] Inducing artificial latency

[John Floren <slawmaster@gmail.com>]

On Tue, Jun 22, 2010 at 2:53 PM, John Floren <slawmaster@gmail.com> wrote:
> On Tue, Jun 15, 2010 at 10:14 PM, Gorka Guardiola <paurea@gmail.com> wrote:
>> On Wed, Jun 16, 2010 at 12:07 AM, erik quanstrom <quanstro@quanstro.net> wrote:
>>>> Last time I needed something similar, I just run a modified iostats.
>>>
>>> how does iostats add latency?
>>>
>>
>> hence the modified.
>>
>
> Hi Gorka
>
> Do you still have your modified iostats around? I'm really not sure
> about the results I get from adding sleeps in the ip code--it takes
> over twice as long to copy a 10M file between my two test machines
> (supposed to have 14ms RTT latency added, ping seems to indicate this)
> than it does to copy from a system running a non-modified kernel to
> go.cs.bell-labs.com (14ms RTT). I'd like to try running the tests with
> a different latency method.
>
> Thanks
>
> John

That was meant to be off-list, but I suck at gmail apparently.

John
--
"With MPI, familiarity breeds contempt. Contempt and nausea. Contempt,
nausea, and fear. Contempt, nausea, fear, and .." -- Ron Minnich