I have seen similar slowness.  Even on a pretty powerful workstation,
a Cygwin shell can take a few seconds to open.  If SSH is taking
significantly longer than running Cygwin locally, you can run 'ssh
-vvv' to try to figure out which stage in the SSH connection sequence
is taking the most time.  You may be able to tweak the sshd_config
settings on the target.  Make sure UseDNS is set to no.

Yes, vcld currently establishes a new connection for every SSH call.
Things should be quicker with VCL 2.3.  I added code to establish a
single SSH connection and then pass commands to it using
Net::SSH::Expect.  This code is in the OS.pm::execute_new()
subroutine.  The code in the repository is not currently configured to
call this but you can test it by uncommenting the following lines:

In OS.pm::execute().
#return execute_new(@_);

In utils.pm::run_ssh_command:
#return VCL::Module::OS::execute($node, $command, $output_level,
$timeout_seconds, $max_attempts, $port, $user);

Also, you'll need to run install_perl_libs.pl or manually install


On Wed, Feb 29, 2012 at 5:59 PM, James O'Dell <jod...@fullerton.edu> wrote:
> Hash: SHA1
> Afaik the vcld process normally starts a new connection each
> time it wants to do something on the client.
> It may batch a few commands during a single session - like when
> it creates a user. But for most part it creates a new connection
> each time.
> On 2/29/2012 2:34 PM, Mike Haudenschild wrote:
>> Hi Jim,
>> I'm working from a new image, so (unfortunately?) Cygwin is already the
>> latest version.
>> I've disabled many of the default items in /etc/profile to try and speed up
>> initial connections.  Do you happen to know if the management node
>> opens/closes the SSH connection for each command it issues, or uses the
>> same SSH session for multiple commands?
>> Many thanks,
>> Mike
>> On Wed, Feb 29, 2012 at 14:42, James O'Dell <jod...@fullerton.edu> wrote:
>> Hey Mike,
>> I had a similar issue with Cygwin.
>> Basically, I installed Cygwin when I created the image. Over
>> the course of time I patched the OS, but not Cygwin.
>> This caused problems.
>> I eventually removed Cygwin, and reinstalled it (had to
>> re-run the Cygwin patch up stuff again).
>> (Pay close attention to who you are actually 'logged in as'
>> when installing Cygwin. I think I needed to be 'root')
>> Anyway, a reinstall of Cygwin helped me out.
>> Hope this helps,
>> __Jim
>> On 2/29/2012 10:41 AM, Mike Haudenschild wrote:
>>>>> Good afternoon, devs --
>>>>> I've been experiencing slower than expected reservation provisioning
>> times
>>>>> on a VCL infrastructure that uses a SAN for all storage (all ESXi, on
>>>>> blades).  I first noticed it when I'd click the "Connect!" button on a
>>>>> reservation and the RDP connection wouldn't open the first time.
>>>>>  Restarting the RDP client 15-30 seconds later, the connection would
>>>>> succeed.
>>>>> Watching vcld.log, I found that connecting to the Cygwin shell from the
>>>>> management node was taking 6-10 seconds (whereas the same connections on
>>>>> servers using local-disk storage take 1-2 seconds).  I can replicate the
>>>>> behavior running ssh -i /etc/vcl/vcl.key <target machine> from the
>>>>> management node.
>>>>> It really hit home when I started a bash shell LOCALLY (with bash --login
>>>>> -i -x) on a target Windows VM and watched how long it took just to get
>> to a
>>>>> bash prompt.  Each of the startup scripts took a long time.  (I'm not
>>>>> running bash-completion, a common complaint about slow Cygwin shell
>>>>> startups.)
>>>>> I *think* -- requesting confirmation of this -- that each time the
>>>>> management node wants to issue a command to a remote computer it
>> initiates
>>>>> a new SSH connection, then closes that connection when the command
>> finishes
>>>>> processing.  Is that accurate?  If so, that would mean that those 6-10
>>>>> seconds would be compounded several times over while the management node
>>>>> prepares the remote computer for my reservation.  I'm currently
>>>>> investigating moving Cygwin into a RAMdisk on the VM images, but that
>> only
>>>>> makes sense if the above assumption about multiple SSH sessions is
>> accurate.
>>>>> The latency on the SAN connection is very low, and ESXi reports that
>>>>> latencies on the virtural disks are slow.  I have /etc/hosts set up, DNS
>>>>> resolves fine, and pings between the management node and VMs are fine.
>>>>> Has anyone else run into any similar behavior with Cygwin?
>>>>> Many thanks,
>>>>> Mike
>>>>> --
>>>>> *Mike Haudenschild*
>>>>> Education Systems Manager
>>>>> Longsight Group
>>>>> (740) 599-5005 x809
>>>>> m...@longsight.com
>>>>> www.longsight.com
> - --
> Jim O'Dell
> Network Analyst
> California State University Fullerton
> Email: jod...@fullerton.edu
> Phone: (657) 278-2256
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