Marc Mamin <M.Mamin@xxxxxxxxxxxx> wrote: > I/O througput decreased from 300MB/s to 160. I don't have any experience with ext4 defrag tools, but just wanted to point out that the difference in performance you cite above is about the same as the difference between accessing data on the outer (and usually first-filled) tracks on a disk drive and the inner tracks. One of the reasons performance falls as a drive fills is that the OS is compelled to use slower and slower portions of the disk. Part of the benefit you are seeing might be due to freeing "fast" tracks and data being relocated there. -- Kevin Grittner EDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
