This also has a good description of how to interpret the results http://thelastpickle.com/2011/04/28/Forces-of-Write-and-Read/
On 25 March 2013 16:36, Brian Tarbox <tar...@cabotresearch.com> wrote: > I think we all go through this learning curve. Here is the answer I gave > last time this question was asked: > > The output of this command seems to make no sense unless I think of it as > 5 completely separate histograms that just happen to be displayed > together. > > Using this example output should I read it as: my reads all took either 1 > or 2 sstable. And separately, I had write latencies of 3,7,19. And > separately I had read latencies of 2, 8,69, etc? > > In other words...each row isn't really a row...i.e. on those 16033 reads > from a single SSTable I didn't have 0 write latency, 0 read latency, 0 row > size and 0 column count. Is that right? > > Offset SSTables Write Latency Read Latency Row Size > Column Count > 1 16033 0 0 > 0 0 > 2 303 0 0 > 0 1 > 3 0 0 0 > 0 0 > 4 0 0 0 > 0 0 > 5 0 0 0 > 0 0 > 6 0 0 0 > 0 0 > 7 0 0 0 > 0 0 > 8 0 0 2 > 0 0 > 10 0 0 0 > 0 6261 > 12 0 0 2 > 0 117 > 14 0 0 8 > 0 0 > 17 0 3 69 > 0 255 > 20 0 7 163 > 0 0 > 24 0 19 1369 > 0 0 > > > On Mon, Mar 25, 2013 at 11:52 AM, Kanwar Sangha <kan...@mavenir.com>wrote: > >> Can someone explain how to read the cfhistograms o/p ?**** >> >> ** ** >> >> [root@db4 ~]# nodetool cfhistograms usertable data**** >> >> usertable/data histograms**** >> >> Offset SSTables Write Latency Read Latency Row >> Size Column Count**** >> >> 1 2857444 4051 0 >> 0 342711**** >> >> 2 6355104 27021 0 >> 0 201313**** >> >> 3 2579941 61600 0 >> 0 130489**** >> >> 4 374067 119286 0 >> 0 91378**** >> >> 5 9175 210934 0 >> 0 68548**** >> >> 6 0 321098 0 >> 0 54479**** >> >> 7 0 476677 0 >> 0 45427**** >> >> 8 0 734846 0 >> 0 38814**** >> >> 10 0 2867967 4 >> 0 65512**** >> >> 12 0 5366844 22 >> 0 59967**** >> >> 14 0 6911431 36 >> 0 63980**** >> >> 17 0 10155740 127 >> 0 115714**** >> >> 20 0 7432318 302 >> 0 138759**** >> >> 24 0 5231047 969 >> 0 193477**** >> >> 29 0 2368553 2790 >> 0 209998**** >> >> 35 0 859591 4385 >> 0 204751**** >> >> 42 0 456978 3790 >> 0 214658**** >> >> 50 0 306084 2465 >> 0 151838**** >> >> 60 0 223202 2158 >> 0 40277**** >> >> 72 0 122906 2896 >> 0 1735**** >> >> ** ** >> >> ** ** >> >> Thanks**** >> >> Kanwar**** >> >> ** ** >> > > -- Thanks Jabbar Azam
