The storage is a direct-attached one. I suspected hardware to be the cause
for a long time but now I think there might be a different reason. That is
because it happened in January and then directly in April. Then we switched
to DR site and it happened the very next day and since then it has been
running fine. So it would be a big coincidence for hardware issue to be the
cause.
Also no logs, dmesg, etc. showing any issues and no such activities like
migration or snapshot backup running. Not even scrub job.
Many Thanks
On 19 April 2018 at 03:52, Ls Cheng <exriscer@xxxxxxxxx> wrote:
I have seen this behaviour for several reasons but all HW related, HBA
saturation, faulty fibre cable, Storage Saturation.
I went through one of this last saturday, I had to call the storage admin
because I was migrating a couple of database from Solaris to Exadata, the
answer as always was that the array was all green light and only 30% CPU
busy but he cut the storage replication just in case, after he cut the
replication my migrations started to fly.
On Wed, Apr 18, 2018 at 7:25 PM, Purav Chovatia <puravc@xxxxxxxxx> wrote:
We are on RHEL 6.6 running a 2-node Oracle 12c RAC.
All of a sudden, for 2-3 minutes, DATADG (asm diskgroup containing all
data files) freezes for 2-3minutes with iostat showing 100% utilisation,
very high svctm and very high write_await. But the r/s, w/s rsec/s and
wsec/s is 0. Meaning no IO but still disk fully busy. So it’s like a freeze.
Has anybody experienced this and can somebody help as to what could be
the reason?
Transparent huge pages were not disabled and general huge pages were not
configured. Now both done.
Many thanks
