state of iscsi_initiator?

[Johan Ström]

On Oct 1, 2008, at 7:35 AM, Danny Braniss wrote:

>>
>> I'm just playing with iSCSI now, on a fresh 7.1-STABLE machine  
>> connected
>> to another FreeBSD box running ports/net/iscsi-target.
>>
>> I am using the latest version 2.1 Initiator from:
>> ftp://ftp.cs.huji.ac.il/users/danny/freebsd/
>>
>> It seems alot better now than when I last tried it.  The speed is
>> constant at around 50MB/s for a single sequential read or write.  It
>> also reconnected very quickly when I restarted the target.  I was  
>> even
>> able to reboot the target box and I/O resumed perfectly once it  
>> finished
>> booting!
>>
>>
>> The speed increased to 80mb/s when I ran two threads, which is  
>> close to
>> the max performance for the network cards in this machine.

Nice, I guess. Wonder how much one can get up to with 1GBit.. Altough  
then I guess thats when the disks will be the limiting factor.
As for recovery, that have been working pretty nice for me to, I've  
been running 2 VMWare machines here (on the same physcal box), one  
with OpenFiler and one with 7.0-STABLE (and 2.0.99 iscsi).
I've been running iozone for a couple of hours, without any crashes or  
so at least.  I also tried rebooting the openfiler in the middle of  
the iozone process with the following results (where the numbers are  
iozone output):

             2048     128    2111    3961  2547261  2190626
             2048     256    4405    4363  2443638  2233342
             2048     512iscontrol[3687]: trapped signal 30
trapped signal 30
iscontrol: supervise going down
iscontrol[3687]: sess flags=2000040d
iscontrol[3687]: Reconnect
errno=61
connect: Connection refused
iscontrol[3687]: Reconnect
iscontrol: supervise starting main loop
       21    4271  1391257  2098062
             2048    1024    4053    4151  2389263  4113514
             2048    2048    3634    5330  2233342  3475985
             4096       4    2860    3947  1648862  1836000

Yes iscontrol was started from the same console earlier. Regarding  
that, I noticed that the 2.1 version had a daemonized version.  is  
there any changelog for 2.1?

>>
>>
>>
>> A couple of minor issues:
>>
>>    1. Trouble shutting down iscontrol - after I kill -9 it stays  
>> around
>> for a minute or more until it finally goes away.
>>
>
> you should kill -1, this does an orderly shutdown of the connection.
> I guess an update to the manual is needed.
>
>>    2. Under very heavy multi-threaded load, the client machine gets
>> sluggish to respond, even to keystrokes on the console.  And if I
>> shutdown the target, even local disk accesses on the client computer
>> stop working after a while.

If you take the target back up, does it wake up again?

>>
>>
>>    (I don't think this is a problem with iSCSI initiator.  I suspect
>> there's something in FreeBSD which pauses all disk I/O if the  
>> length of
>> outstanding requests is too high, can anyone shed some light on  
>> this?)
>>
> I've noticed slugishness when a heavy fsck is running in the  
> background - not
> iscsi related, so it seems that heavy disk IO is using up resources,  
> but
> then again, the CPU is working :-)



Thanks for your input :)