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giltene / wrk2

A constant throughput, correct latency recording variant of wrk
Apache License 2.0
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Failure to meet Rate #28

Open koliaskostas opened 8 years ago

koliaskostas commented 8 years ago

I do: ./wrk -t10 -c100 -d30s -R2000 --latency http://192.168.56.103/

however the rate is never more than 450 r/s

I can only achieve the desired rate for really low R values like 100 e.g.

The page I am hitting is static and fairly small (few Kb).

There are no socket errors or time-outs generated by the experiments.

I run ubuntu 16.4 with 4.4.0-31-generic kernel in vm with 4 cores and 10GB RAM.

Any chance that I have to enable or disable something for wrk2 to work properly?

ahothan commented 8 years ago

We're using wrk in a vm and have no problem going over 1000rps. The issue you have might be caused by your VM kernel timer config. How is your kernel timer configured?

$ egrep 'CONFIG_HZ|TIMERS' /boot/config-$(uname -r) CONFIG_HIGH_RES_TIMERS=y CONFIG_HZ_250=y CONFIG_HZ=250

mrafsyam commented 6 years ago

Hi, Hows the kernel timer affect the rps?

adamf663 commented 6 years ago

In linux, unless you go "tickless", config_hz determines how often the OS can do task switching. I ran @ 1000hz until tickless was offered.