> On Dec. 18, 2014, 4:19 p.m., Josh Elser wrote: > > core/src/main/java/org/apache/accumulo/core/file/rfile/MetricsGatherer.java, > > line 36 > > <https://reviews.apache.org/r/29176/diff/1/?file=795044#file795044line36> > > > > Why the concurrent maps? I don't see anything in these changes that > > would require it now, do you have plans for something else in the future? > > Jenna Huston wrote: > These keep separate metrics. One for the density of that metric in the > locality group and the other for how many blocks in that locality group this > visiblity is seen in. > > Josh Elser wrote: > I understand why you're using a map, I'm confused about why you need a > concurrent datastructure. This appears to be single-threaded. > > Jenna Huston wrote: > The AtomicLongMap made it easier to increment counters of visibilities. > With a regular map you have to delete what is there and then put in a new > entry with the incremented count.
Ok, thanks for the explanation. The extra synchronization imposed by the maps is likely not of any concern, I was just worried that I was missing something else. - Josh ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/29176/#review65499 ----------------------------------------------------------- On Dec. 18, 2014, 9:37 p.m., Jenna Huston wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/29176/ > ----------------------------------------------------------- > > (Updated Dec. 18, 2014, 9:37 p.m.) > > > Review request for accumulo. > > > Bugs: ACCUMULO-3420 > https://issues.apache.org/jira/browse/ACCUMULO-3420 > > > Repository: accumulo > > > Description > ------- > > Added an option to PrintInfo to get visibility metrics. Prints the number of > times a visibilty is seen in each locality group. Also shows how many blocks > in the locality group have his visibiltiy. > > > Diffs > ----- > > core/src/main/java/org/apache/accumulo/core/file/rfile/MetricsGatherer.java > PRE-CREATION > core/src/main/java/org/apache/accumulo/core/file/rfile/PrintInfo.java > 43586dd > core/src/main/java/org/apache/accumulo/core/file/rfile/RFile.java 9dcb3a5 > > core/src/main/java/org/apache/accumulo/core/file/rfile/VisMetricsGatherer.java > PRE-CREATION > > Diff: https://reviews.apache.org/r/29176/diff/ > > > Testing > ------- > > Tested with a few RFiles that I made. > > > Thanks, > > Jenna Huston > >
