[Info-vax] VMS to VMS data copy options/performance when losing a DECnet link

[Jeffrey H. Coffield]

On 04/14/2022 01:17 PM, Rich Jordan wrote:
> On Thursday, April 14, 2022 at 1:52:54 PM UTC-5, Jeffrey H. Coffield wrote:
>> On 04/14/2022 11:31 AM, Rich Jordan wrote:
>>> On Thursday, April 7, 2022 at 6:24:03 PM UTC-5, Rich Jordan wrote:
>>>> Customer has decided to turn off "legacy" DECnet support on their network. They currently use DECnet for copies between two nonclustered integrity servers that are on different IP subnets/VLANs and have Cisco doing whatever magic it does to make DECnet appear local. THis is Phase IV, not DECnet over IP.
>>>>
>>>> Is there any documentation on relative performance for bulk data transfer with preliminary data archiving (ie ZIP or backup to a local archive file so not transferring lots of individual files) on VMS using FTP/SFTP versus using NFS as the transfer mechanism? I know details matter and I don't have them yet but is one likely to be enough different that it is worth pursuing a test? Which won't be trivial given equipment availability...
>>>>
>>>> Thanks for any info
>>>
>>>
>>> Well, tried various combinations of the TCP protocol settings (like NODELAY_ACK), the FTP logicals for initial and append allocations, the FTP window size, etc. FTP is doing 1.4 to 1.64Mbps (that last due to /NODELAY_ACK) and won't go any higher. SFTP is supposed to be slower but we'll try it anyway. For now going to locate iPerf ports for VMS and run some tests with it to see what actual throughput we are getting between the sites.
>>>
>> We had to move large save sets over FTP when a system was replaced with
>> another system at a different location and we used the following setting
>> to speed up the transfers:
>>
>> $ TCPIP
>> sysconfig -r socket sb_max=2000000
>> sysconfig -r socket somaxconn=10240
>> sysconfig -r socket sominconn=10240
>> sysconfig -r inet tcp_sendspace=300000 tcp_recvspace=300000
>> sysconfig -q socket
>> sysconfig -q inet tcp_sendspace tcp_recvspace
>>
>> I know I didn't figure this out but I don't remember where I found these
>> settings.
>>
>> Jeff
>> www.digitalsynergyinc.com
>
> Jeff, thanks will take a shot with those.
>
> I'm currently testing remote VMS ftp to/from the PC server that the main system sends its nightly backup savesets to, and getting about 4.8 Mbps, so about 3x the VMS to VMS rate.   The main system gets about 15Mbps to that PC but they are in the same datacenter.  Still slow for gigabit but it fits their timing windows.
>
> We'll see if the above parameters make a difference between the remote VMS server and the PC first; I can't make changes to the production box until the weekend, especially if a reboot is needed (will have to check)
>
> Thanks again
>

No reboot necessary. I set up those commands to be executed on system 
startup

Jeff