G'day,
I just noticed that the raw values of this metric have different units
on Linux and Solaris.
solaris> pminfo -d disk.dev.read_bytes
disk.dev.read_bytes
Data Type: 64-bit unsigned int InDom: 75.0 0x12c00000
Semantics: counter Units: byte
^^^^
linux> pminfo -d disk.dev.read_bytes
disk.dev.read_bytes
Data Type: 32-bit unsigned int InDom: 60.1 0xf000001
Semantics: counter Units: Kbyte
^^^^^
Both PMDAs are reporting in the units they claim to, so I guess there's
no bug there.
But I've been using pmdumptext, whose manpage says
UNIT CONVERSION
All metrics that have the semantics of counters are automatically con‐
verted to rates over the sample time interval. In interactive mode,
pmdumptext will also change the units of some metrics so that they are
easier to comprehend:
o All metrics with space units (bytes to terabytes) are scaled to
bytes. Note that 1024 bytes with be represented as 1.02K, not
1.00K.
Yet I see pmdumptext reporting the Linux numbers in Kbyte/sec not
byte/sec like I was expecting. So what's wrong here: the manpage, the
code, or my reading of the manpage?
--
Greg.
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