Messages in this thread | | | Subject | Re: [PATCH RFC] [INET]: Get cirtical word in first 64bit of cache line | From | Eric Dumazet <> | Date | Sun, 02 Dec 2012 09:20:11 -0800 |
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On Sun, 2012-12-02 at 21:25 +0800, Ling Ma wrote: > Hi Eric, > > Attached benchmark test-cwf.c(cc -o test-cwf test-cwf.c), the result > shows when last level cache(LLC) miss and CPU fetches data from > memory, critical word as first 64bit member in cache line has better > performance(costs 158290336 cycles ) than other positions(offset 0x10, > costs 164100732 ) in cache line, the performance is improved by 3.6% > in this case. > cpu-info is also involved too. > > Thanks > Ling
Thanks Ling.
Note that I was more interested by the case we read more fields per cache line, like we do in tcp lookups. (skc_daddr, skc_rcv_saddr, skc_bound_dev_if, skc_net).
I made changes to net-next to prepare your patch.
You'll have to move both skc_rxhash & skc_portpair before the skc_addrpair.
I have to fix an endianness sparse problem, I'll send a patch for this in a separate thread right now.
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