2. What is the nature and description of the request? Customer has a large number of systems and they all kick off their nightly cronjobs (such as mlocate, logrotate, etc) at the same time, resulting in very high I/O wait. They would like cron to offer the ability to randomize jobs across a given time period. 3. Why does the customer need this? (List the business requirements here) To prevent hundreds of systems from kicking off the same job at the same time, putting excessive load on storage, network, etc 4. How would the customer like to achieve this? (List the functional requirements here) They gave us a set of example patches, but they do not completely solve the problem. These patches would configure SPLAY for *every* job on the system, but they want the ability to selectively enable it for certain jobs. The patches to demonstrate the feature: --- /usr/bin/run-parts.orig 2006-07-14 23:05:38.000000000 -0500 +++ /usr/bin/run-parts 2010-10-28 13:18:38.000000000 -0500 @@ -1,6 +1,7 @@ #!/bin/bash # run-parts - concept taken from Debian +. /etc/sysconfig/crond # keep going when something fails set +e @@ -15,6 +16,11 @@ exit 1 fi +if [ -n $SPLAY ] +then + sleep `expr $RANDOM % $SPLAY` +fi + # Ignore *~ and *, scripts for i in $1/*[^~,] ; do [ -d $i ] && continue --- /etc/sysconfig/crond.orig 2009-12-11 03:31:19.000000000 -0600 +++ /etc/sysconfig/crond 2010-10-28 13:20:47.000000000 -0500 @@ -7,3 +7,4 @@ # from this tr(1) set : [@!:%-_.,:alnum:] # otherwise mailing is not attempted. CRONDARGS= +SPLAY=600 So, if you configured a job for "0 4 * * *" and set SPLAY=7200, jobs would be randomly scattered across the 2 hour period from 4am-6am. Ideally, their example would be extended to allow you to set this per cronjob. 5. For each functional requirement listed in question 4, specify how Red Hat and the customer can test to confirm the requirement is successfully implemented. Set SPLAY for the relevant cronjob on multiple servers. Observe that they were randomized across the SPLAY period. 6. Is there already an existing RFE upstream or in Red Hat bugzilla? No 7. How quickly does this need resolved? (desired target release) 5.8 8. Does this request meet the RHEL Inclusion criteria (please review) Yes 9. List the affected packages vixie-cron