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Re: Problem reports for version control systems

On 2021-05-02 16:32, Anders Magnusson wrote:
Den 2021-05-02 kl. 15:57, skrev Johnny Billquist:
On 2021-05-02 13:51, Anders Magnusson wrote:
Den 2021-05-02 kl. 13:44, skrev Johnny Billquist:

I suspect what is commonly the problem here is related to the fact that cvs has such a phase at the beginning where it is scanning through the file system, which can take quite a while. Some NAT devices along the path sometimes have timeouts on existing connections that if no traffic is happening for a while, they are dropped, even though there hasn't been any FINs on the connection. So a connection that just don't have any traffic for a while are hit by this, which is exactly the pattern you have with cvs.

I've seen the same effect on a simple telnet session, where ssh survives fine. And there it's just that when the connection is idle, telnet is not creating any traffic at all, while ssh do generate a bit of traffic even if there is no activity.

So one obvious solution is to use something like ssh as a carries for the cvs traffic, if possible, or else see if some kind of keepalives can be enabled on a connection, to defeat NAT and similar devices which aggressively drop connections on which there is no traffic for a while. (Or, of course, if there is a NAT you have control over, you might be able to change how it behaves...)
This is quite common, yes.
I ususlly add ssh keepalive to ssh_config for all hosts to avoid this problem (which may occur, as written, when doing cvs update).

And as a "fun" fact. On my 4000/90, it takes about 3h after I start a cvs update until I actually start having any network traffic... In total it takes something like 8h to do a cvs update on /usr/src. (I guess I'm a bit masochistic is still insisting on trying to do things on my VAXen...)
Have you tried it on the 8650? :-)

Last time I did manage, I think it was close to a day. That with RA73 drives. But you know there's been problems with having two unibuses lately, and so on. So it's been quite a while since I actually managed to much of anything natively on that machine. :-(

Another reason I'd like to get gcc working native again. Also trying to get a chance to fix things on the 8650. Not sure how much longer we will be able to keep that machine around ready to run. We might need to shrink our locales soon...


Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email:             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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