Planned downtime: Filesystem test (2019-04-11 22:00 UTC)

[loftar]

Will forums be up?

They will, but during the final phase the account server will be down for a few moments, meaning it will not be possible to log in. Should be a fairly short while, though.

[Hasta]

@loftar thanks for keeping us posted. Hope you'll make do on your estimates of 30-60 min downtime.

[loftar]

The copying is going a bit slower than expected, so it might be longer than announced. It's going a bit up and down, so I can't really accurately gauge an ETA at this point.

[shubla]

I think there was some discussion about some new cool filesystem that was being used earlier but maybe I remember wrong.

The discussion was about bcache, which isn't a filesystem but a caching layer (when given drives of different speed characteristics).
Regarding a cool filesystem I tried to pitch the use of ZFS to loftar a while back.

@loftar: good luck, please keep up posted on the results. Though I must admit that I don't see a reason why switching to ext could help.
Fun fact: had to discard an otherwise intact SSD (Intel datacenter class) today as writes to it took 240ms on average...

Bcache? So the server is really running off HDD and ssd is only used for caching?
Why? Wouldn't it be faster to just use ssd?

Or if this is not the case, what is bcache needed for.

[Granger]

Bcache? So the server is really running off HDD and ssd is only used for caching?
Why? Wouldn't it be faster to just use ssd?

Or if this is not the case, what is bcache needed for.

https://en.wikipedia.org/wiki/Automated_tiered_storage

[loftar]

Bcache? So the server is really running off HDD and ssd is only used for caching?
Why? Wouldn't it be faster to just use ssd?

The entire game data should fit very well on the SSDs, so in practice the server should pretty much be using the SSDs only.

Or if this is not the case, what is bcache needed for.

Storage management, pretty much. Though the game data fits on the SSDs, other parts of the filesystems only very barely do, and I don't want to bother with manually allocating them to hard drives or SSDs. Most of the rest of the data is pretty rarely used, though, and shouldn't put much strain on bcache.

[loftar]

Most of the data is copied, and only the account data remains, so I'll shut down the account server in order to transfer it. The forums will stay up, but logins and other such functionality will be broken while doing so.

[Genabeton]

Hey, guys. You seem to know what you're doing. We have no reason to worry

[Unisow]

Until you go, something went wrong ...

[loftar]

There, the account data was copied and the account server is running again. Will restart the game server again in less than five minutes.