> On June 20, 2013, 10:20 p.m., Ben Mahler wrote: > > src/slave/constants.cpp, line 32 > > <https://reviews.apache.org/r/11100/diff/2/?file=309822#file309822line32> > > > > Ok, so 10 per second maximum. > > > > Let's say we run 4 tasks per minute, that have 50 files / directories > > to remove. That's 200/minute -> 3.33 files / minute. Seems like we might > > need to implement a strategy for handling a growing queue size of removals > > (by having a dynamic interval), can you add a TODO signaling this potential > > issue? > > Vinod Kone wrote: > Agreed on the need to be smarter about this. But not sure a growing queue > size implies a need to do it faster. What we are trying to do here is to > maintain a constant disk i/o. Just because there are more files to remove, > doesn't mean we can do it faster. It could increase the disk i/o to the point > of affecting the slave. I think we need smartness in figuring our the right > interval. Does that make sense? > > >
I think number of files to delete is a weak proxy for disk i/o. Is this to prevent a storm of random iops introducing latency to other processes? Wouldn't this be better phrased as i/o prioritization rather than rate limiting the deletion: opportunistically process the file deletion queue as fast as possible but yield to others when they have any i/o. Include baseline i/o to ensure it's sufficiently serviced. Furthermore, couldn't this prioritization be pushed to the kernel i/o scheduler itself? Have either ionice(1) or cgroups/blkio been considered? - Ian ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/11100/#review22201 ----------------------------------------------------------- On June 21, 2013, 12:44 a.m., Vinod Kone wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/11100/ > ----------------------------------------------------------- > > (Updated June 21, 2013, 12:44 a.m.) > > > Review request for mesos, Benjamin Hindman and Ben Mahler. > > > Description > ------- > > The purpose of the incinerator is to move items to trash and empty trash in > rate-limited manner. It is designed to work across slave restarts. > > > Diffs > ----- > > src/Makefile.am 933743593d8de2fcc412d2f771a4cbc1e6fd2884 > src/slave/constants.hpp 901fdf220a902de9241511393530eb19fdfc3244 > src/slave/constants.cpp e8d16ca3307249a8b49720eaf8dcb0e7555fca7a > src/slave/incinerator.hpp PRE-CREATION > src/slave/incinerator.cpp PRE-CREATION > src/tests/gc_tests.cpp 174580086370f61be369f7a212d62531e87e6f01 > > Diff: https://reviews.apache.org/r/11100/diff/ > > > Testing > ------- > > make check > > > Thanks, > > Vinod Kone > >
