So I''m trying to figure out what it is that makes clustered allocation so much faster than unclustered allocation. E.g., for a nearly quiescent filesystem with as little as 90MB of metadata, balance-md (from another patch I posted today) takes some 4.5 seconds (worst case 6s, best case 4s) with clustered allocation, while with -o nocluster it takes some 6.5s (best case 6s, worst case 7s). With -o mincluster, introduced by the patch below (by no means intended for merging, it''s far too hackish) it''s some 0.1s faster than with -o nocluster, but nothing really significant, and I didn''t even take care of locking last_ptr. So I conclude it''s not remembering the search starting point that makes -o cluster faster. Anyhow, since this is slightly faster than unclustered allocation, I suppose we could introduce something along these lines for the -o nocluster case, no? -- Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/ You must be the change you wish to see in the world. -- Gandhi Be Free! -- http://FSFLA.org/ FSF Latin America board member Free Software Evangelist Red Hat Brazil Compiler Engineer