OSCER users,
REMINDER:
OSCER scheduled maintenance outage Wed Feb 28 8am-midnight.
Systems affected: supercomputer, OURdisk, OURcloud,
OURRstore tape archive.
Details are earlier in this e-mail thread.
---
IMPORTANT IMPORTANT IMPORTANT IMPORTANT!!!
Before the scheduled maintenance outage starts on
Wed Feb 28 8:00am:
Jobs that wouldn't finish before the scheduled maintenance
outage starts won't be able to start at all, until after the
scheduled maintenance outage has ended (planned for
Wed night at midnight).
Because, by this approach, such jobs can run for
the full wall clock time limit that they've requested.
So, if you want a job to run before the scheduled
maintenance outage begins, then in your batch scripts,
you might need to reduce the amount of wall clock
time limit you request.
(Once the maintenance period ends, this won't apply
any more.)
If you have jobs that you've already submitted that are
pending in the queue, then you might want to reduce
their requested wall clock time limit, to give them
a chance to start before the scheduled maintenance
outage begins.
The command is:
scontrol update JobId=######## TimeLimit=DD-HH:MM:SS
except REPLACE ######## with the job ID number, and
REPLACE DD-HH:MM:SS with 2-digit number of days,
2-digit number of hours (beyond the number of days),
2-digit number of minutes (beyond the days and hours)
and 2-digit number of seconds (beyond the days, hours
and minutes).
You have to pick a wall clock time limit short enough that
the job can run to its time limit before the start of the
scheduled maintenance outage.
For example, suppose job 123456 had requested 48 hours of
wall clock time limit, but now there are less than 48 hours
before the start of the scheduled maintenance outage.
So job 123456 won't be able to run until after the
scheduled maintenance outage ends.
But, we could change the requested wall clock time limit
for job 123456 to, for example, 30 hours, like this:
scontrol update JobId=123456 TimeLimit=01-06:00:00
In that case, job 123456 would have a *CHANCE*
(but *NOT A GUARANTEE*) to run before the outage starts.
Henry
OSCER users,
OSCER will hold a scheduled maintenance outage Wed Feb 28 8am-midnight.
Systems affected: supercomputer, OURdisk, OURcloud, OURRstore tape archive.
The OSCER team will perform the following maintenance items (time permitting),
in the following priority order:
(1) Shift to a new user database instance.
(2) Update Linux on OURdisk.
(3) Decommission our one older OURdisk monitor node (we have
5 newer monitor nodes, which are already in production alongside
the one older one, and the recommendation is to have either 3 or 5).
(4) Time permitting, upgrade one of the condominium compute nodes to
25GE (from its current 10GE).
(5) Time permitting, reconfigure the routing of the supercomputer's
Infiniband-to-Ethernet gateway appliances, and shift onto these
IB-to-Ethernet gateway appliances the network traffic of
(i) one compute node (for testing) and (ii) one of our scratch subsystems.
(6) Time permitting, shift all nodes to the IB-to-Eth gateway appliances.
We apologize for the inconvenience -- as always, our goal is to make
OSCER resources even better!
---
Director, OU Supercomputing Center for Education & Research (OSCER)
Associate Professor, Gallogly College of Engineering
Adjunct Associate Professor, School of Computer Science
OU Information Technology
The University of Oklahoma
Engineering Lab 212, 200 Felgar St, Norman OK 73019
405-325-5386 (office), 405-325-5486 (fax), 405-245-3823 (cell),
http://www.oscer.ou.edu/