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Diffstat (limited to 'cddl/contrib/dtracetoolkit/Examples/rfileio_example.txt')
| -rw-r--r-- | cddl/contrib/dtracetoolkit/Examples/rfileio_example.txt | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/cddl/contrib/dtracetoolkit/Examples/rfileio_example.txt b/cddl/contrib/dtracetoolkit/Examples/rfileio_example.txt new file mode 100644 index 000000000000..dcce81ee4da7 --- /dev/null +++ b/cddl/contrib/dtracetoolkit/Examples/rfileio_example.txt @@ -0,0 +1,94 @@ +The following are demonstrations of the rfileio.d script. + + +rfileio.d prints file system statistics by file, + + # ./rfileio.d + + Read IOPS, top 20 (count) + /lib/ld.so.1 logical 2 + /devices/pseudo/clone@0:ptm logical 4 + /usr/bin/grep logical 4 + /devices/pseudo/pts@0:3 logical 4 + /extra1/contents physical 1700 + /extra1/contents logical 11582 + + Read Bandwidth, top 20 (bytes) + /devices/pseudo/pts@0:3 logical 3 + /devices/pseudo/clone@0:ptm logical 92 + /lib/ld.so.1 logical 212 + /usr/bin/grep logical 269 + /extra1/contents physical 48115712 + /extra1/contents logical 94865162 + + Total File System miss-rate: 50% + ^C + + $ ls -l /extra1/contents + -rw-r--r-- 1 root root 94865162 Nov 2 21:08 /extra1/contents + +The /extra1/contents file was read using the grep command. The output shows +that half of the contents was returned from the cache, the other half from disk +(50% miss-rate). It is 94,865,162 bytes in size, which can be seen both in +the ls -l output and the logical read() bytes reported by rfileio.d. There +were 11,582 logical read() calls, which the disk driver satisfied by using +1,700 disk events (aggregation). + + + +The following demonstrates many files being read. + + # ./rfileio.d + + Read IOPS, top 20 (count) + /usr/bin/amd64/glib-mkenums logical 4 + /usr/bin/amd64/glib-genmarshal physical 4 + /usr/bin/amd64/gdk-pixbuf-query-loaders logical 4 + /usr/bin/amd64/ls logical 5 + /usr/bin/amd64/pargs logical 5 + /usr/bin/amd64/ps logical 5 + /usr/bin/amd64/gconf-merge-tree physical 6 + /usr/bin/amd64/cputrack logical 6 + /usr/bin/amd64/gconftool-2 physical 6 + /usr/bin/amd64/prctl logical 6 + /usr/bin/amd64/prstat logical 6 + /usr/bin/amd64/glib-genmarshal logical 7 + /usr/bin/amd64/truss physical 8 + /usr/bin/amd64/sort logical 9 + /usr/bin/amd64/prex logical 10 + /usr/bin/amd64/gconf-merge-tree logical 13 + /usr/bin/amd64/mdb physical 15 + /usr/bin/amd64/gconftool-2 logical 15 + /usr/bin/amd64/truss logical 26 + /usr/bin/amd64/mdb logical 63 + + Read Bandwidth, top 20 (bytes) + /usr/bin/amd64/prctl logical 36784 + /usr/bin/amd64/prctl physical 36864 + /usr/bin/amd64/prstat logical 44760 + /usr/bin/amd64/prstat physical 45056 + /usr/bin/amd64/glib-genmarshal logical 46064 + /usr/bin/amd64/glib-genmarshal physical 46080 + /usr/bin/amd64/cputrack logical 46912 + /usr/bin/amd64/cputrack physical 47104 + /usr/bin/amd64/sort logical 65120 + /usr/bin/amd64/sort physical 65536 + /usr/bin/amd64/prex logical 80968 + /usr/bin/amd64/prex physical 81920 + /usr/bin/amd64/gconf-merge-tree logical 113592 + /usr/bin/amd64/gconf-merge-tree physical 122880 + /usr/bin/amd64/gconftool-2 logical 129208 + /usr/bin/amd64/gconftool-2 physical 139264 + /usr/bin/amd64/truss logical 246360 + /usr/bin/amd64/truss physical 262144 + /usr/bin/amd64/mdb logical 627456 + /usr/bin/amd64/mdb physical 638976 + + Total File System miss-rate: 81% + ^C + +The miss-rate was 81%, meaning we are returning around 20% of the data from +the cache. Details for the top 20 files read by-bytes and by-count are listed; +this shows the /usr/bin/amd64/mdb file was read() 63 times, causing 15 disk +reads, and while 627,456 bytes were requested, 638,976 bytes were read from +disk (the extra bytes are due to read-ahead and file system metadata). |