noamineo wrote on Oct 28
th, 2020 at 9:40pm:
So apparently the game worlds stayed down extra long today because SSG literally forgot to turn them back on.
Then downtime for Sarlona was extended because, according to jerry:
Now, we know DDO's servers were (badly)virtualized a few years ago. The theory back then was that the virtualization was meant to reduce the game's hardware footprint by replacing 8 independent machines with some smaller number of virtual hosts.
Oh, come on be serious a minute, you really think that a game
server is actually one single server ? At a glance from the old olgs I keep and doing a few wild assed guesses, there's at least 3 servers for one game server : the login server, the game server itself and the backend database server that stores our characters. I'd add a fourth one the queing server but I've never been able to prove it was a separate function from the login server.
Once upon a time all those where physical boxes... with a front end network switch and a backend network switch... Now they are all virtualized on the same physical box with front end vlans and back end vlans in teh virtualizer switching function.
noamineo wrote on Oct 28
th, 2020 at 9:40pm:
However, the fact that 1 individual server can stay down "due to hardware maintenance" would seem to punch a hole in that theory.
They just did a RAM upgrade on all the servers and Sarlona hardware failed to come up with a checksum error on a stick... ( really wild guess ) So they are troubleshooting it.
Since what I called Sarlona abovev is a box that contains 3 or 4 ( maybe more ) VMs defining Sarlona it's not far from truth.
noamineo wrote on Oct 28
th, 2020 at 9:40pm:
Here's my new belief: MMOs in particular are usually optimized at the hardware-level, E.G. the code is actually written around the server's specific architecture and memory topology. This is because in order to get the kind of lag-free gameplay we all so desperately want, making the server software work is a lot more complicated than just "put a faster CPU in there and give it more RAM".
Well compared to 2005 servers the servers we have right now are light years ahead in capacity to the point that more RAM and more Core can work...( and not Faster CPUs... Modern CPUS are generally slower than the 2006 ones ) You don't even need to upgrade the software to multicore... you just assign a core to a virtual server in the hypervizor.
noamineo wrote on Oct 28
th, 2020 at 9:40pm:
This is why things like WoW getting a server upgrade is such a big deal: its not just a matter of installing the software on a new machine. It means rewriting the code for that hardware, a task requiring elite veteran programmers to carry out.
Server upgrade is always a big thing... To the point that I once spent a week end in 8 Hours shifts to perform a software upgrade ( yep no hardware involved, but critical telecom equipment... so critical that we twinned it before the operation so that the twin took over while we upgraded the system ). Getting the 99.9999% uptime in a yearout of any system ( aka Telecom Grade ) does not come cheap.
noamineo wrote on Oct 28
th, 2020 at 9:40pm:
Enter DDO, which is apparently funded entirely by a blind orphan sitting on the sidewalk with a tin cup. Hardware ages, companies stop producing spares, and support contracts expire(and I feel bad for you if you've ever had to work in a data center trying to keep out of warranty hardware running - its not fun). A few years back, SSG was in a pickle: they could no longer feasibly keep the DDO server hardware running, but they also no longer had the technical expertise in-house to migrate to a new hardware platform.
The simple solution to this problem was virtualization. Build a virtual server that mimics the hardware DDO was written to run on. In practice, you would never do something like that in a production environment; but in practice no one would ever hire jerry, so it makes sense in context.
This would then mean each individual server still has it's own physical machine to run on, but that hardware is running a hypervisor which in turn runs the virtual server. This is far less effective than running the servers "on metal" - but it does work, AND it does get you into a place where some deficiencies can be made up simply by cramming in more CPU/memory/disk I/O resources.
Keyword there is "some" of course.
we don't really know in details how a given DDO Server is built... but taking into account the fact that the bare metal nowadays is lightyears better than the 2006 one... Even without multicore/multithreading software you can assign a core to a specific function ( say login ) another one to another function ( say database ) and another one to a third function ( the game itself ) and still have power ( and RAM to spare )
SweetKitten wrote on Oct 29
th, 2020 at 1:01pm:
LOL, since decades no application server software has been optimized at the hardware-level.
Definitely, the time when optimization at hardware level was something belongs to before Y2K. Since then it's the Time of Visual This or That that spew code generated by moving boxes around on a screen and linking them together. Said code being horribly unoptimized... even in the source code. ( so don't expect it to be better in the compiled code )
But who cares... we have computing power to waste, RAM to waste and Mass storage to waste... now try to make some graphical library for a VGA screen fit in less than 4K and we will talk about code optimization.