MigrationHeuristic is a parameter for EXA to know when to "migrate" pixmaps to video memory. Possible values are "always", "greedy", and "smart". It can be applied by adding a specific line to the divice section of your xorg.conf. For example: [[!format txt """ Section Device ... Option "MigrationHeuristic" "greedy" ... EndSection """]] Currently the default is "always" ("smart" on older xorg).

(jwstolk, xorg 1.4.0.90, NV15, 2008-01-28: rendering a scaled image in firefox took +/- 60 seconds. switching from always to greedy fixed this.)

For best performance, use:

x NV04/05 NV10 NV20 NV30 NV40 NV50
Value ? ? ? ? Always ?