strange response time question

Björn Döbel doebel at os.inf.tu-dresden.de
Wed Aug 6 23:56:41 CEST 2014


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On 06.08.2014 23:51, Yuxin Ren wrote:
> I did not measure min value. The avg is around 5000 cycs, and my
> machine is 2.8GHz.
> 
> Client and server are in different core.

- - And are these cores on the same socket or on different ones?

- - Are the timestamp counters between these cores synchronized?
  => To be safe you might want to measure the roundtrip time from
     client to server and back as then you use the same hardware
     TSC.

- - Did you disable the usual suspects for System Management Mode
  interruptions (for instance Legacy USB Support, which is often
  provided as a feature by your BIOS)?

Bjoern

- -- 
Dipl.-Inf. Bjoern Doebel    Mail:  doebel at tudos.org
TU Dresden, OS Chair        Phone: +49 351 463 38 799
Noethnitzer Str. 46         Fax:   +49 351 463 38 284
01187 Dresden, Germany      WWW:   http://www.tudos.org/~doebel
- --
"When the seagulls follow the trawler, it's because they think
 sardines will be thrown into the sea." (Eric Cantona)
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