fsstat in latest OpenSolaris

I've updated my test machine to the latest OpenSolaris build.

I used the bfu archives this time. Normally I wait for it to make it into Solaris Express (SXCR) and jumpstart, but this release has two feature I wanted to investigate, and I want to try them out as soon as I can.

The two features in question are the Java binding to DTrace, and the new fsstat utility and associated kstat support. More on DTrace once I get jkstat updated to integrate with it, but I wanted to mention a little more about fsstat.

Now, I'm just a user, but I've played with fsstat a little and looked at the code, so I've got a little bit of understanding of what it's doing.

On its own, fsstat will give filesystem activity for the various filesystem types:

 new  name   name  attr  attr lookup rddir  read read  write write
 file remov  chng   get   set    ops   ops   ops bytes   ops bytes
1.22K   606    63 1.99M   569  10.2M 37.8K  993K  502M  216K  152M ufs
    0     0     0 7.73K     0  14.8K   722 8.65K 3.18M   290 6.91K proc
    0     0     0     1     0     10     0     0     0     0     0 nfs
    0     0     0     0     0      0     0     0     0     0     0 zfs
    0     0     0 87.1K     0      0     0     0     0     0     0 lofs
14.6K 2.95K 11.5K 30.8K    37  43.5K    26 32.9K 32.9M 45.9K 34.5M tmpfs
    0     0     0 3.05K     0      0     0    32 5.25K     0     0 mntfs
    0     0     0     0     0      0     0     0     0     0     0 nfs3
    0     0     0     0     0      0     0     0     0     0     0 nfs4
    0     0     0     6     0      0     0     0     0     0     0 autofs

If you give it a filesystem as an argument, it will show that:

# fsstat /tmp /var/run /etc/svc/volatile
 new  name   name  attr  attr lookup rddir  read read  write write
 file remov  chng   get   set    ops   ops   ops bytes   ops bytes
  251   233     2 1.10K    21    719    26    29 34.9K    60 36.7K /tmp
   20     0     0    44     8  16.8K     0     0     0     6    67 /var/run
14.5K 2.72K 11.6K 29.8K     8  26.4K     0 32.9K 32.9M 46.0K 34.5M /etc/svc/volatile

and it takes the normal interval and count arguments.

These numbers are all backed by kstats. For example:

# kstat unix:0:vopstats_ufs
module: unix                            instance: 0
name:   vopstats_ufs                    class:    misc
        crtime                          76.4978722
        naccess                         559104
        naddmap                         1280864
        nclose                          514400
        ncmp                            5179654
        ncreate                         1222
        ndelmap                         1276280
        ndispose                        1788458
        ndump                           0
        ndumpctl                        0
        nfid                            0
        nfrlock                         6953
        nfsync                          1641
        ngetattr                        1550291
        ngetpage                        5904478
        ngetsecattr                     2882
        ninactive                       30404
        nioctl                          114402
        nlink                           18
        nlookup                         10861279
        nmap                            1024824
        nmkdir                          17
        nopen                           479509
        npageio                         14
        npathconf                       70555
        npoll                           477742
        nputpage                        39301
        nread                           1031796
        nreaddir                        38829
        nreadlink                       785043
        nrealvp                         65352
        nremove                         602
        nrename                         29
        nrmdir                          4
        nrwlock                         1292387
        nrwunlock                       1293855
        nseek                           213405
        nsetattr                        531
        nsetfl                          179084
        nsetsecattr                     26
        nshrlock                        0
        nspace                          12
        nsymlink                        16
        nvnevent                        0
        nwrite                          223174
        read_bytes                      530866166
        readdir_bytes                   18340192
        snaptime                        9588.8833902
        write_bytes                     159609739

Now, that's a lot of data about what's going on.

The kstat names aren't spectacularly obvious. They all start with unix:0:vopstats_ with the unique identifier tagged onto the end. This can either be a filesystem type (ufs, lofs, nfs, zfs are some examples) or the id of a filesystem mountpoint. So in /etc/mnttab you might see

/dev/dsk/c0t1d0s0 / ufs  rw,intr,...,dev=1d80008

(I've trimmed this for brevity). So the kstat you need to query for statistics on the root filesystem in this case is called unix:0:vopstats_1d80008.

And that's pretty much it. Now to get some more tools to make sense of all this new information!