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 Net::SSH::Expect. -Andy On Wed, Feb 29, 2012 at 5:59 PM, James O'Dell <jod...@fullerton.edu> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > 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 > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.9 (MingW32) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iEYEARECAAYFAk9Orc4ACgkQREVHAOnXPYRK4gCfZAUN9WqrP8RJQ3SdukIcs9I8 > 6PsAoKa3Q1f8hzkoiJo8hx8N6nwWOcaV > =7AEx > -----END PGP SIGNATURE-----
