Call for testers: patch to convert dc(4) to busdma

[Wilko Bulte]

Could it be there is something fishy with mbuf handling?

I ran netperf from my DS10 Alpha box towards a 4-stable
netperf-receiver (called freebie)

As in:

ds10#ls
netperf                 tcp_range_script        udp_rr_script
netserver               tcp_rr_script           udp_stream_script
snapshot_script         tcp_stream_script
ds10#./tcp_range_script freebie

------------------------------------
Testing with the following command line:
/usr/local/netperf/netperf -l 60 -H freebie -t TCP_STREAM -i 10,2 -I 99,3 --
-m 1 -s 32768 -S 32768

TCP STREAM TEST to freebie : +/-1.5% @ 99% conf. : histogram

After some time one gets:

Out of mbuf address space!
Consider increasing NMBCLUSTERS
All mbufs or mbuf clusters exhausted, please see tuning(7).
Out of mbuf address space!
Consider increasing NMBCLUSTERS
All mbufs or mbuf clusters exhausted, please see tuning(7).

Initially things were like:

ds10#netstat -m
mbuf usage:
        GEN cache:      0/0 (in use/in pool)
        CPU #0 cache:   2195/2240 (in use/in pool)
        Total:          2195/2240 (in use/in pool)
        Mbuf cache high watermark: 512
        Maximum possible: 18176
        Allocated mbuf types:
          2195 mbufs allocated to data
        12% of mbuf map consumed
mbuf cluster usage:
        GEN cache:      0/0 (in use/in pool)
        CPU #0 cache:   2189/2192 (in use/in pool)
        Total:          2189/2192 (in use/in pool)
        Cluster cache high watermark: 128
        Maximum possible: 9088
        24% of cluster map consumed
4944 KBytes of wired memory reserved (99% in use)
0 requests for memory denied
0 requests for memory delayed
0 calls to protocol drain routines

and after the machine ran out of buffers it displayed:

ds10#netstat -m
mbuf usage:
        GEN cache:      0/0 (in use/in pool)
        CPU #0 cache:   9061/9088 (in use/in pool)
        Total:          9061/9088 (in use/in pool)
        Mbuf cache high watermark: 512
        Maximum possible: 18176
        Allocated mbuf types:
          9061 mbufs allocated to data
        50% of mbuf map consumed
mbuf cluster usage:
        GEN cache:      0/0 (in use/in pool)
        CPU #0 cache:   9058/9072 (in use/in pool)
        Total:          9058/9072 (in use/in pool)
        Cluster cache high watermark: 128
        Maximum possible: 9088
        99% of cluster map consumed
20416 KBytes of wired memory reserved (99% in use)
0 requests for memory denied
0 requests for memory delayed
0 calls to protocol drain routines
ds10#

During the test run there was a steady increase in the % for the cluster
map.

Wilko

-- 
|   / o / /_  _   		wilko at FreeBSD.org
|/|/ / / /(  (_)  Bulte