On Mon, Jul 1, 2019 at 9:05 PM Mark Nelson <mnelson@redhat.com> wrote:
On 7/1/19 1:39 AM, kefu chai wrote:
hi Mark,
i am working on using cbt for testing crimson. as you might known, crimson-osd is currently using a variant of memstore as its object store backend. so it'd be very easy for crimson-osd to run out of memory, as the default run "time" of cbt radosbench is 300 seconds.
currently, each radosbench run is composed of 3 steps:
1. prefill // optional, enabled if "prefill_time" or "prefill_objects" is set 2. write. 3. read // optional, enabled if "write_only" is not test
the pain point is that the run times for write and read step are specified using the same setting -- "time".
so, i am wondering if it's okay to add an option named "read_only" to skip the "write" step to let the prefill to prepare the testbench for the read test. so we can specify the time for prefilling and the time for read separately?
Ah, that makes sense!
great! i will come up with a PR soon!
as an alternative, we could have an option for "write_time", which defaults to "time" if not specified, but if it takes precedence over "time" if specified. and it's "0", the "write" step will be skipped.
what do you think?
What would you think about "time" as the default but it can be overridden with either "prefill_time", "write_time", or "read_time" (defaulting to None, ie use time) for the specific stages? That way you can specify a long global time when testing a specific number of objects?
that makes sense to me! will add this in another commit in the same PR. thanks Mark!
Mark
-- Regards Kefu Chai