disk diagnostics

[Pieter Dumon]

Wow, not too fast. I don't have access to my machine right now (I'm at
work), so I will post detailed stats later (timed rm, top output, ...)
- no servers (web,mail,smb,....) are running
- no other users present
- no cron jobs or other daemons or other processes apart from the
standard system processes and X+KDM running.
- disk room enough for what I'm trying to do, only HDD access to that
HDD needed.
- it's an AMD Sempron 3100+, with Dragonfly on the old disk
- the 25 minutes was a subjective quantification. But it's O(10min).
- DFly-preview 1.5.4, but got the same problem with older versions
- I did not want to say it is a bug in DFly, no far from that, it just
should be some hardware problem or a configuration issue or something
stupid.
If I remember well, the rm process is spending a lot of time in the
IOWAIT status, but I'm not sure anymore. So, wait for more info to
come later.
thanks already,

Pieter

On 7/26/06, Bill Hacker <wbh at xxxxxxxxxxxxx> wrote:
Simon 'corecode' Schubert wrote:

> Bill Hacker wrote:
>
>> Warren Hull 25 minutes delay comes in, and I/O tuning doesn't cover
>> that. Too big a number for where it is being reported as happening.
>>
>> Either something else - probably something *basic* but simply
>> overlooked - is placing demands on that storage system, or the
>> 'problem' has been misreported.
>
>
> softupdates?  writing meta data with sync will be really slow.
>
> cheers
>  simon
>
No, not *that* slow, not even on K6-2-500 with 256 MB of SDRAM, where I have
done it on a production FreeBSD 4.8 web & mx box for donkey's years (too small
to hold a RAID). DFLY may not have focused on that area, but should not be 2 or
3 orders of magnitude slower than 4.9/4.9 BSD.
Especially not that slow on a scripted dirtree rm -Rf

I'd want to see what is in the ~/messages and other logs, (rampant I/O errors?),
what, if anything was mounted from the CD's, where mounted, and what the path
was at the time - likewise RAMDISK and if df showed one or more mounts
at/near/over 100%+ of capacity, memory and swap stats.... etc.  The 'usual
suspects'.
The time involved hints at CD's being spun up, paths searched, found not to
contain <whatever>, rewind.... or some partition being pushed over 100%
temporarily. Folsks cramming multiple OS test installs onto media all too rarely
pay attention to temporary needs. The 8+ GB needed for building OpenOffice from
source caught even this old dog flatfooted, for example.
Otherwise, ATA I/O is too 'universal' in use to hide a DFLY bug of such
magnitude for very long, so the paucity of related reports says it is a local
'headspace' issue...
Bill