[Mauiusers] Fairshare issue (P4 HyperThreading ?)

Claus Jeppesen jeppesen at memphys.sdu.dk
Tue Sep 7 00:29:21 MDT 2004


Dear Mauiusers,

We have a 960 (Pentium4, linux) node cluster of which 304 have
HyperThreading enabled. We are also making extensive use of Fairshare for
allocating resources on the cluster.

Our scheduling will only allow one node to be assigned to one job by setting
the parameters:

NODEACCESSPOLICY        SINGLETASK
JOBNODEMATCHPOLICY      EXACTNODE

Prompted by an apparent "overutilization" of the cluster: I.e. in a given
fairshare window it seems that it's possible to have more CPU-hours spend than
what is calculated by multiplying the lifetime of a fairshare window with
the number nodes, I would like to ask:

a) Is this overutilization associated with MAUI "counting" 2 PROC's per
   HyperThreaded enabled node ?

b) In general, is there a way of telling MAUI that in the Fairshare calculation
   that one hour spend on a given node should only be counted as X% hour ?

   This would be of interest in heterogeneous clusters (like ours with a
   mixture of 3,2 2,6 and 2,0 GhZ Pentium4 nodes).

Thanx,

Claus.

--
Claus Jeppesen
Memphys Center, SDU
Campusvej 55
5230 Odense M, Denmark
Ph: +45-65503475 Fax: +45-66158760

----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.



More information about the mauiusers mailing list