# Network slowdown



## dewarrn1 (Jun 7, 2010)

Hi all,

     I've got a persistent problem with network slowdown that I haven't been able to diagnose.  Immediately after a (re)boot, everything seems fine, but the longer my homebrew, all-in-one router/server stays on, the slower things get on both my wired and wireless LANs.  Transfer speeds suffer, pings get longer, etc.

I'm running 8.0 with ZFS, my facing-out NIC uses nfe, my LAN-facing NIC is a gigabit Intel card using em, and my wireless NIC is using ral.  What should I be looking at to address this?  Thanks in advance!


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## hydra (Jun 7, 2010)

Maybe try net-mgmt/iftop to see the current utilization. Don't you see anything strange in the logs ?


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## User23 (Jun 11, 2010)

i answered the same question here: http://forums.freebsd.org/showthread.php?t=14975


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## dewarrn1 (Jun 16, 2010)

Thanks for the suggestions, guys!  I'm embarrassed to report that posting on this forum seems to have cured the problem without any further action on my part, but if the system starts acting up again I'll definitely refer to your advice.  Much appreciated!


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## dewarrn1 (Jun 24, 2010)

OK, took a while, but the issue has come up again.  I took a look at iftop's output, and while it confirms how slow things are, it doesn't provide any more specific insight into the cause of the problem.  dmesg is clean except for the failure of a "conftest" process, and I have no idea whether that happened recently or not.  I'm not seeing anything in any of the other logs, but maybe I'm not looking in the right places.  netstat returns the following:


```
Name    Mtu Network       Address              Ipkts Ierrs    Opkts Oerrs  Coll
ral0   2290 <Link#1>      00:1f:1f:3f:76:f3        0     0  3020787  7852     0
em0    1500 <Link#2>      00:1b:21:2e:45:95  9245179     0 12550847     0     0
em0    1500 192.168.0.0   192.168.0.1        8859163     - 11134650     -     -
nfe0   1500 <Link#3>      00:01:29:d4:2d:6b 14703660     0  3878806     0     0
nfe0   1500 173.19.224.0/ 173-19-224-254.cl   150208     -   394003     -     -
plip0  1500 <Link#4>                               0     0        0     0     0
lo0   16384 <Link#5>                           66709     0    66709     0     0
lo0   16384 fe80:5::1     fe80:5::1                0     -        0     -     -
lo0   16384 localhost     ::1                      0     -      616     -     -
lo0   16384 your-net      localhost             1949     -    66093     -     -
wlan0  1500 <Link#6>      00:1f:1f:3f:76:f3  2468708  1074  2898243  4130     0
wlan0  1500 192.168.1.0   192.168.1.1          47213     -    52856     -     -
pflog 33152 <Link#7>                               0     0    22120     0     0
```

If I'm reading that right, ral0 and wlan0 (which are the wireless NIC and it's alias) are showing some errors, but nothing else.  My netstat -m output is:


```
603/942/1545 mbufs in use (current/cache/total)
576/578/1154/25600 mbuf clusters in use (current/cache/total/max)
576/448 mbuf+clusters out of packet secondary zone in use (current/cache)
0/58/58/12800 4k (page size) jumbo clusters in use (current/cache/total/max)
0/0/0/6400 9k jumbo clusters in use (current/cache/total/max)
0/0/0/3200 16k jumbo clusters in use (current/cache/total/max)
1304K/1623K/2927K bytes allocated to network (current/cache/total)
0/0/0 requests for mbufs denied (mbufs/clusters/mbuf+clusters)
0/0/0 requests for jumbo clusters denied (4k/9k/16k)
0/0/0 sfbufs in use (current/peak/max)
0 requests for sfbufs denied
0 requests for sfbufs delayed
0 requests for I/O initiated by sendfile
0 calls to protocol drain routines
```

tcpdumps on all interfaces come up clean, no packets lost.  Unfortunately, I need to get some work done and will be rebooting the system in order to do so.  If any of this information provides clues, I'd love to hear about them.  Thanks in advance!


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