Re: [Condor-users] Site-wide want_remote_io=false possible?

[Matthew Farrellee <matt@xxxxxxxxxx>]

Carsten Aulbert wrote:
> Hi,
>
> brief questions around want_remote_io:
>
> (1) Is it possible to enable this site-wide, e.g. change the default
> setting to False. I guess it is but so far I have failed to find that,
> how can that be done?

You can use SUBMIT_EXPRS[1], e.g.

WantRemoteIO = FALSE
SUBMIT_EXPRS = WantRemoteIO

Then, unless a user specifies want_remote_io = true explicitly, they'll 
get want_remote_io = false.


> (2) On our system users have their home file system under NFS and then
> can also use a local directory which is also automountable via NFS. Does
> the user need to avoid writing to the local disk under all circumstances
> when want_remote_io is set to false?

This would depend on the file transfer policy. If "a local directory" is 
the same as "the local disk", then chances are you don't need to worry 
about file transfer. If you write to a location only on the execute node 
and do not perform file transfer, you won't get your data back, because 
those writes are actually happening on the execute node now, not on the 
submit node.


> The reason why we want to disable that is that our submit machines are
> under very heavy load when large standard usinverse jobs are run and we
> suspect remote io playing a key role here.
>
> Thanks in advance
>
> Carsten

Best,


matt

[1] http://www.cs.wisc.edu/condor/manual/v7.1/3_3Configuration.html#15375