Hi Chris, On Thu, Jan 04, 2018 at 04:34:51PM +0900, Chris Mi wrote: > Currently in tc batch mode, only one command is read from the batch > file and sent to kernel to process. With this patchset, we can accumulate > several commands before sending to kernel. The batch size is specified > using option -bs or -batchsize. > > To accumulate the commands in tc, client should allocate an array of > struct iovec. If batchsize is bigger than 1, only after the client > has accumulated enough commands, can the client call rtnl_talk_msg > to send the message that includes the iov array. One exception is > that there is no more command in the batch file. > > But please note that kernel still processes the requests one by one. > To process the requests in parallel in kernel is another effort. > The time we're saving in this patchset is the user mode and kernel mode > context switch. So this patchset works on top of the current kernel. > > Using the following script in kernel, we can generate 1,000,000 rules. > tools/testing/selftests/tc-testing/tdc_batch.py > > Without this patchset, 'tc -b $file' exection time is: > > real 0m15.555s > user 0m7.211s > sys 0m8.284s > > With this patchset, 'tc -b $file -bs 10' exection time is: > > real 0m13.043s > user 0m6.479s > sys 0m6.504s > > The insertion rate is improved more than 10%.
Did you measure the effect of increasing batch sizes? I wonder whether specifying the batch size is necessary at all. Couldn't batch mode just collect messages until either EOF or an incompatible command is encountered which then triggers a commit to kernel? This might simplify code quite a bit. Cheers, Phil
