On Mon, Feb 12, 2007 at 01:12:57PM +0000, Alan (alan@xxxxxxxxxxxxxxxxxxx) wrote: > > I'm sure others would want them then for their favourite system call combo > > too. If they were really useful it might make more sense to have a batch() > > system call that works for arbitary calls, but I'm not convinced yet > > it's even needed. It would be certainly ugly. > > batch() would possibly make a lot of sense in terms of the fibril/thread > based removal for the need for all the AIO stuff, just to provide a > natural way to group and order sequences of synchronous operations into > asynchronous groups. > > I am extremely sceptical about the need for aio_sendfile_path since with > sendfile/sendpath hacking around there didn't seem to be much gain. > > I'm even more sceptical of the header buffer stuff as while other OS's do > that as a hack to make TCP packetising work we simply fixed the root > problem with TCP_CORK Well, that does not matter that much - that syscall is an example of how kevent AIO state machine works - it trivially allows to have async open/send/sendfile/close like aio_senfile_path. I would remove header too (it was not there in the first release, added on request), but the whole idea of async open/send/close seems natural for web-like workloads, when user should not even care about proper state machine. Having batch() mode would be good too - with kevent state machine it is quite trivially: req = kaio_add_call(NULL, first_call) kaio_append_call(req, second_call); kaio_append_call(req, third_call); ... kaio_schedule_req(req); Yes, state machine handling requires additional code, but when it ends up in faster processing implementation complexities deserve its price. > Alan -- Evgeniy Polyakov - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
