>> On Thu, 11 Mar 2010 08:32:20 +0330, Mehdi Salehi <ezzobad AT GOOGLEMAIL DOT
>> COM> said:
> Say there is not disk storage pool and two clients from the two tape
> storage pools accidentally sent their backups exactly at the same
> time. Which one graps the tape drive first?
"exactly" the same time, isn't. One of them is first, even if it's a
matter of which thread gets executed first.
In any case, there's only one lock for a tape drive. When that DRIVE
is moved from IDLE to WAITING FOR MEDIA, the other process is out of
luck, it will wait.
- Allen S. Rout
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