# asynchronous nfs mount with amd



## jrm@ (Dec 30, 2012)

Is it possible to have amd(8) nfs mount asynchronously?


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## jrm@ (Dec 30, 2012)

Some more information...

This is the default /etc/amd.map.

```
/defaults type:=host;fs:=${autodir}/${rhost}/host;rhost:=${key}
*               opts:=rw,grpid,resvport,vers=3,proto=tcp,nosuid,nodev
```
I guessed adding async to the opts would work, but here I see there is a sync option, but no async option.


```
% mount
...
storage:/mnt/mirror1 on /.amd_mnt/storage/host/mnt/mirror1 (nfs, nosuid)
...
```


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## jrm@ (Dec 31, 2012)

*Comparison of read/write speeds when nfs mounting with and without amd*

Hello self;

With amd using the default /etc/amd.conf:

```
% mount | grep home
storage2:/tank/home on /.amd_mnt/storage2/host/tank/home (nfs, nosuid)

home % dd if=/dev/zero of=testfile bs=512k count=6000
3145728000 bytes transferred in 34.969986 secs (89955083 bytes/sec)

home % dd if=testfile of=/dev/null bs=512k count=6000
3145728000 bytes transferred in 27.096053 secs (116095432 bytes/sec)
```

Without amd:

```
% grep home /etc/fstab
storage2:/tank/home /home nfs rw,noauto,async 0 0

/home % mount | grep home
storage2:/tank/home on /home (nfs, asynchronous)

/home % dd if=/dev/zero of=testfile bs=512k count=6000     
3145728000 bytes transferred in 27.515901 secs (114324005 bytes/sec)

dd if=testfile of=/dev/null bs=512k count=6000
3145728000 bytes transferred in 29.362761 secs (107133249 bytes/sec)
```

I'm not sure how useful these tests are given I'm not clear what mount options amd is using and that I'm reading from /dev/zero and writing to /dev/null.


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