sir,
i have a doubt on NAPI(feature which was
introduced in linux 2.6.3).In which polling is used
instead of interrupts when packets arrive at the
network card.
i did not find any performance difference between a
non NAPI driver and a NAPI driver(this may be because
i used large packets).Both of them showed 94Mbps,but
when i reduced the "DMA receive ring size" from 32k to
8k, i got a performance difference. The ordinary
driver without NAPI (rtl8139too in 2.4.20 linux)
showed 72Mbps and the NAPI driver (rtl8139too in
2.6.3) showed 94Mbps,both having their ring size at
8k.The packet size i used was same as before.
why is this difference when the ring size is
reduced.
waiting for your reply.
prashant
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