[ovs-dev] [PATCH] timeval: Provide a variation for time/warp command.

[Ben Pfaff]

On Fri, Jun 13, 2014 at 11:08:37AM -0700, Gurucharan Shetty wrote:
> On Thu, Jun 12, 2014 at 3:35 PM, Ben Pfaff <blp at nicira.com> wrote:
> > On Fri, Jun 06, 2014 at 10:04:31AM -0700, Gurucharan Shetty wrote:
> >> The new command is of the form 'time/warp LARGE_MSECS MSECS'.
> >> It advances the current monotonic time by LARGE_MSECS. This is done MSECS
> >> at a time in each run of the main thread. This gives other threads
> >> time to run after the clock has been advanced by MSECS.
> >>
> >> The old command would continue to work.
> >>
> >> Rationale: On Windows, process creation is slower. When we have tests
> >> that run 'ovs-appctl time/warp MSECS' hundreds of times in a for loop,
> >> the time it takes to complete the test increases. This is specially
> >> true for bfd tests. For e.g, the 11 bfd tests would take 3.5 minutes
> >> to complete before this change and now takes a little less than 2 minutes.
> >>
> >> Signed-off-by: Gurucharan Shetty <gshetty at nicira.com>
> >
> > In struct large_warp, it seems a little awkward to store 'warp' as a
> > timespec.  I am surprised that it is not just an integer number of
> > milliseconds.
> >
> I dilly-dallied a bit on it and was expecting an opinion. I will add
> the following addition
> and send a V2.

I like this better.

I think that this:
> +    if (c->large_warp.total_warp - c->large_warp.warp >= 0) {
could be written as
> +    if (c->large_warp.total_warp >= c->large_warp.warp) {