On 2002-07-11 17:12 +0000, Bosko Milekic wrote: > On Thu, Jul 11, 2002 at 01:56:08PM -0700, Luigi Rizzo wrote: > > example: userland does an 8KB write, in the old case this requires > > 4 clusters, with the new one you end up using 4 clusters and stuff > > the remaining 16 bytes in a regular mbuf, then depending on the > > relative producer-consumer speed the next write will try to fill > > the mbuf and attach a new cluster, and so on... and when TCP hits > > these data-in-mbuf blocks will have to copy rather than reference > > the data blocks... > > This is a good observation if we're going to be doing benchmarking, > but I'm not sure whether the repercussions are that important (unless, > as I said, there's a lot of applications that send exactly 8192 > byte chunks?).
This is not true only for 8192 byte-sized writes. Anything that uses a block size >2048 near a power of 2 will have the same problem. Writes that use 2048 bytes, 4096, 8192, 16384, ... will all have this very same problem :/ To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-net" in the body of the message
