Folks ! I have a batch application that writes approx. 4 million rows into a narrow table. I am using JDBC addBatch/ExecuteBatch with auto commit turned off. Batch size is 100. So far I am seeing Postgres take roughly five times the time it takes to do this in the Oracle. I have played with many parameters. Only one that seems to have any affect is fsync - but thats only 10% or so. Initially I got the warning that checkpoints were happening too often so I increased the segments to 24. Warnings stopped, but no real improvement in performance. Is postgres really that slow ? What am I missing ? Here are the changes to my postgressql.cong file. shared_buffers = 768MB work_mem = 256MB maintenance_work_mem = 128MB fsync = off checkpoint_segments = 24 autovacuum = on Thank you, -Sanjay -- View this message in context: http://www.nabble.com/Postgres-batch-write-very-slow---what-to-do-tf3395195.html#a9452092 Sent from the PostgreSQL - performance mailing list archive at Nabble.com.