Re: [libvirt] [PATCH 1/3] qemu: Move memory limit computation to a reusable function

Il 02/07/2013 13:40, Jiri Denemark ha scritto: > On Tue, Jul 02, 2013 at 12:34:44 +0200, Paolo Bonzini wrote: >> Il 02/07/2013 08:34, Jiri Denemark ha scritto: >>> I'm not sure if that's >>> the right think to do or not but it's certainly better than before when >>> memory locking limit completely ignore the need for VRAM and per-disk >>> cache. Unfortunately, the original formula was suggested by Avi, who >>> moved to new challenges. Perhaps others could jump in and share their >>> opinions (Paolo? :-P). >> >> I think the disk cache should not be counted in the memory locking >> limit. > > Hmm, I guess you're right. However, we're computing a limit and I feel > like allowing QEMU to lock a bit more shouldn't make any bad effects or > am I wrong? On the other hand, it would be pretty easy to let the > function know what kind of limit it's going to compute each time it's > called. Yes, both ways are fine. But you should at least have a comment. >> Apart from that, the code you posted below makes sense. > > Even with the 1GB addition for VFIO? I have to admit I'm a bit ignorant > of VFIO but shouldn't that limit be derived from the number of attached > devices If that would be the amount of memory reserved for BARs (PCI memory mapped regions), 1 GB should be enough. Let's just ask Alex Williamson.