[Info-vax] Where to locate software

[Kerry Main]

> -----Original Message-----
> From: Info-vax [mailto:info-vax-bounces at info-vax.com] On Behalf Of
> Stephen Hoffman via Info-vax
> Sent: 12-Jun-16 12:58 PM
> To: info-vax at info-vax.com
> Cc: Stephen Hoffman <seaohveh at hoffmanlabs.invalid>
> Subject: Re: [New Info-vax] Where to locate software
> 
> On 2016-06-12 14:09:08 +0000, Kerry Main said:
> 
> > Perhaps  look at some small company like Facebook and see what they
> > have chosen and the reasons why: VCS is Mercurial - a centralized VCS:
> > https://code.facebook.com/posts/218678814984400/scaling-mercurial-
> at-facebook/
> >
> >
> 
> Oh, and Mercurial (Hg) is a DVCS.   One which happens to work on
> OpenVMS too — though far from integrated with any of the OpenVMS
> development tools — and where git tends to be somewhat more
> problematic
> due to its dependencies on the Linux and bash environments.   Yes, I
> know about jgit.
> 

Ooops, you are right that Mercurial is a DVCS - I mistook the central 
server they use as an example of a centralized VCS.

Having stated this, when you see people talk about the reasons for a
DVCS, they typically raise the following questions (with what I believe
are answers from an OpenVMS perspective)

Q: what happens if the central server is down? 
A: Use a Dev cluster and cluster aware VCS. That way You not only get 
availability but scaling with batch based compiles and builds by simply 
adding additional blades/servers as required. To the developers, the
cluster looks like a single system. Servers can be patched or FW upgraded
etc. transparently to the dev community.

Q: what happens if the network is slow or unavailable?
A: Networks today are much more reliable and faster than in the past. 
In addition, most Tier3 sites typically also have dual redundancies built 
in at all levels. This includes different WAN providers feeding the DC 
so issues with a single provider can be minimized. 

Again - there are times and places for both types of VCS's.

However, companies should not be blindly adopting VCS's like GIT or 
other distributed VCS's just to be fashionable in the developer world. 

Regards,

Kerry Main
Kerry dot main at starkgaming dot com