On Wednesday 25 A > > It doesn't seem to enable sg merging? Since you have enough space > > that should work. > We actually have a patch to do sg merge. In my test, it doesn't have any > performance gain.
It probably depends on the IO device and how slow or fast it is at walking sg lists. I saw a small win (few percent gain) some years ago with MPT Fusion chips > > A GFP_ATOMIC mempool is rather useless. mempool only works if it can block > > for someone else freeing memory and if it can't do that it's not failsafe. > > I'm afraid you need to revise the allocation strategy -- best would be > > to somehow move the memory allocations outside the spinlock paths > > and preallocate if possible. > The problem is pci_map_single and friends usually called with interrupt > disabled or spin locked, so we must use GFP_ATOMIC. Yes I know, but the mempool still won't work. The design is b0rken. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
