Re: workarounds for nscd and java

From: Paul H. Hargrove (PHHargrove_at_lbl_dot_gov)
Date: Wed Jul 22 2009 - 08:41:48 PDT

  • Next message: Guy Coates: "Re: workarounds for nscd and java"
    Guy,
    
      Thanks very much for the info.  For the next release we have already 
    implemented a run-time disable of nscd, provided by another user, in 
    BCLR's initialization code.  However, that has a weakness if other code 
    runs any ncsd-assisted query prior to BLCR's shared library 
    initializer.  So, your ncsd config info will be useful.
      As for the java work-around, this is the first solution we've heard of 
    and are graetful.  Can you point us at a URL for this info.
    
    -Paul
    
    
    Guy Coates wrote:
    > Hi,
    >
    > There are a couple of additional workarounds that might be useful to add to the
    > FAQs about checkpointing with nscd:
    >
    > Why do I get "vmadump: mmap failed: /var/db/nscd/[something]" in the system logs?)
    >
    > and java jobs:
    >
    > (Why do I get "vmadump: mmap failed: /tmp/hsperfdata_[user]/[pid]" in the system
    > logs?)
    >
    > You can disable the nscd filedescriptor passing behaviour which confuses BLCR by
    > adding the following options to your nscd.conf file:
    >
    > shared                  passwd          no
    > shared                  group           no
    > shared                  hosts           no
    >
    > (The only place this seems to be documented is
    > http://anusf.anu.edu.au/~djh900/nscd.html)
    >
    >
    > The sun java runtimes can be made BLCR friendly by adding the following option
    > when calling java:
    >
    >  -XX:-UsePerfData
    >
    > This will prevent the creation of the /tmp/hsperfdata* files.
    >
    > Cheers,
    >
    > Guy
    >
    >   
    
    
    -- 
    Paul H. Hargrove                          PHHargrove_at_lbl_dot_gov
    Future Technologies Group                 Tel: +1-510-495-2352
    HPC Research Department                   Fax: +1-510-486-6900
    Lawrence Berkeley National Laboratory     
    

  • Next message: Guy Coates: "Re: workarounds for nscd and java"