checkpoint write errors

Hi all;

we're seeing the below errors over and over in the logs of one of our postgres databases. Version 8.4.22

Anyone have any thoughts on correcting/debugging it?

Maybe I need to run a REINDEX on whatever table equates to "base/1029860192/1029863651"?  If so how do I determine the db and table for "base/1029860192/1029863651"?

LOG:  checkpoint starting: time
ERROR:  xlog flush request 2571/9C141530 is not satisfied --- flushed only to 2570/DE61C290
CONTEXT:  writing block 4874 of relation base/1029860192/1029863651
WARNING:  could not write block 4874 of base/1029860192/1029863651
DETAIL:  Multiple failures --- write error might be permanent.

Thanks in advance