Re: Byte ordering

On 16/10/2024 07:36, Terje Mathisen wrote:

George Neuner wrote:

On Tue, 15 Oct 2024 18:40 +0100 (BST), jgd@cix.co.uk (John Dallman)
wrote:
>

In article <vekb2f$1co97$6@dont-email.me>, ldo@nz.invalid (Lawrence
D'Oliveiro) wrote:
>

On the other hand, some stubborn holdouts are still fond of
microkernels -- you just have to say the whole idea is pointless,
and they come out of the woodwork in a futile attempt to disagree

>
The idea is impractical, not pointless. A hybrid kernel gives most of the
advantages of a microkernel to its developers, and avoids the need for
lots of context switches. It doesn't let you easily replace low-level OS
components, but not many people actually want that.

>
Actually, I think there are a whole lot of people who can't afford
non-stop server hardware but would greatly appreciate not having to
waste time with a shutdown/reboot every time some OS component gets
updated.
>
YMMV.

 This is _exactly_ (one of) the problem(s) cloud infrastructure solves: As soon as you have more than a single instance of a particular server/service, then you replace them in groups so that the service sees zero downtime even though all the servers have been updated/replaced.
 

That's fine - /if/ you have a service that can easily be spread across multiple systems, and you can justify the cost of that.  Setting up a database server is simple enough.
Setting up a database server along with a couple of read-only replications is harder.  Adding a writeable failover secondary is harder still.  Making sure that everything works /perfectly/ when the primary goes down for maintenance, and that everything is consistent afterwards, is even harder.  Being sure it still all works even while the different parts have different versions during updates typically means you have to duplicate the whole thing so you can do test runs.  And if the database server is not open source, your license costs will be absurd, compared to what you actually need to provide the service - usually just one server instance.
Clouds do nothing to help any of that.
But clouds /do/ mean that your virtual machine can be migrated (with zero, or almost zero, downtime) to another physical server if there are hardware problems or during hardware maintenance.  And if you can do easy snapshots with your cloud / VM infrastructure, then you can roll back if things go badly wrong.  So you have a single server instance, you plan a short period of downtime, take a snapshot, stop the service, upgrade, restart.  That's what almost everyone does, other than the /really/ big or /really/ critical service providers.