Sync of multiple devices

Discussion created by basti1101 on Jun 22, 2011
Latest reply on Jul 9, 2011 by Jawed


I have one kernel on multiple devices at the same time. Currently i enqueue one kernel and than a read-command to check the return value of the kernel. The kernel currently only contains the md5-algorithm.

My Problem is that every read causes a gab in the timeline on the GPU. The Cpu doesn't have these gabs.

I can avoid these gabs with enqueing multiple kernels but in this case i had to sync the devices and i don't know how. I want to interrupt the kernels on other devices, if the solution is found on one device.

I am using a Radeon HD 5850 with Catalyst 11.6 on Win7 x64 with an Core i7 920 as CPU.

A screenshot of the profileroutput can be found at:  here

Does anybody know how to sync within multiple devices or why the GPU has these gabs?