Kazu Yamamoto
Hi,
I measured the performace of GHC head, 7.8.3 and 7.8.3 + Ben's patch set.
Server: witty 8080 -r -a -s +RTS -N<n> *1 Measurement tool: weighttp -n 100000 -c 1000 -k -t 19 http://192.168.0.1:8080/ Measurement env: two 20 core (w/o HT) machines directly connected 10G
Here is result (req/s):
-N<n> 1 2 4 8 16 --------------------------------------------------------- head 92,855 155,957 306,813 498,613 527,034 7.8.3 86,494 160,321 310,675 494,020 510,751 7.8.3+ben 37,608 69,376 131,686 237,783 333,946
head and 7.8.3 has almost the same performance. But I saw significant performance regression in Ben's patch set.
This may be due to lacking INLINEs on definitions added in GHC.Event.Internal [1]. I'm currently in the middle of reproducing these results on an EC2 instance to confirm this. So far the results look much more consistent than my previous attempts at benchmarking on my own hardware. Cheers, - Ben [1] https://github.com/bgamari/ghc/tree/event-rework-7.10