On Wed, Aug 05, 2020 at 06:14:16PM +0300, Max Gurtovoy wrote: > > On 8/5/2020 4:16 PM, Leon Romanovsky wrote: > > On Wed, Aug 05, 2020 at 03:12:30PM +0300, Max Gurtovoy wrote: > > > Add performance optimization that might slightly improve small IO sizes > > > benchmarks. > > > > > > Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx> > > > --- > > > drivers/infiniband/ulp/isert/ib_isert.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > I find the expectation from "unlikely/likely" keywords to be overrated. > > > > When we introduced dissagregate post send verbs in rdma-core, we > > benchmarked likely/unlikely and didn't find any significant difference > > for code with and without such keywords. > > > > Thanks > > Leon, > > We are using these small optimizations in all our ULPs and we saw benefit in > large scale and high loads (we did the same in NVMf/RDMA). > > These kind of optimizations might not be seen immediately but are > accumulated. > > I don't know why do you compare user-space benchmarks to storage drivers. Why not? It produces same asm code and both have same performance characteristic. > > Can you please review the code ? There is nothing to review here, the patch is straightforward, I just don't believe in it. > > Sagi, > > Can you send your comments as well ? > >
