Andreas Dilger wrote: > On 2009-11-01, at 02:03, Thomas Roth wrote: > >> Could this situation, 10 full OSTs out of 200, >> lead to a significant drop in performance? >> Before, we could usually get the full 110MB/s >> or so over the 1Gbit/s ethernet lines of the clients. >> That had dropped to about 50%, but we did not >> find any other odd thing than the filling levels of >> the OSTs. >> > > Yes, this is entirely possible. If the OST is very > full, then it takes longer to find free blocks. >
Longer to find them, and less likely to allocate large contiguous free blocks, so the disk IOs are smaller with more seeks. Kevin _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
