Messages in this thread | | | Date | Mon, 4 Mar 2002 10:46:09 -0700 | From | "Jeff V. Merkey" <> | Subject | Re: Gigabit Performance 2.4.19-preX - Excessive locks, calls, waits |
| |
On Mon, Mar 04, 2002 at 03:04:00PM +0000, Alan Cox wrote: > > provided for review. Recommend a minumum change of increasing > > the sysctl_hot_list_len from 128 to 1024 by default. I have reviewed > > Good way to kill low end boxes. It probably wants sizing based on system > size and load monitoring. > > > NetWare always created ECB's (Event Control Blocks) at the max size > > of the network adpapter rather than trying to allocate fragment > > elements on the fly the way is being done in Linux with skb's. > > Thats up to the network adapter. In fact the Linux drivers mostly do > keep preloaded with full sized buffers and only copy if the packet size > is small (and copying 1 or 2 cache lines isnt going to hurt anyone)
There's an increase in latency. For my application, I have no problem keeping around a local patch that corrects this behavior if folks don't feel it needs fixing. From everything I've ever done in this space, having needless alloc/free calls in a performance intensive path that requires low latency like a Lan driver is not a good thing.
I am idle most of the time since I have eliminated all of the copy activity by using SCI in the system. This is why it's idle most of the time. Were I using the IP stack code in Linux proper, the utilization would be through the roof.
:-)
Jeff
> > > 28044 default_idle 584.2500 > > You spent most of your time asleep 8) > > > 1117 __rdtsc_delay 34.9062 > > Or doing delays > > > 927 eth_type_trans 4.4567 > > And pulling a line into L1 cache - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |