Re: [Gluster-users] Questions about healing

yes it's configurable with: network.ping-timeout and default is 42 seconds I believe. On 22 May 2016 at 03:39, Kevin Lemonnier wrote: > > Let's assume 10.000 shard on a server being healed. > > Gluster heal 1 shard at once, so the other 9.999 pieces would be read > >

Re: [Gluster-users] Questions about healing

2016-05-21 23:51 GMT+02:00 Kevin Lemonnier : > But with 3.7.11 the shards are getting locked only during the heal of that > specific > shard. That means even if all your shards needs healing, each shard is only > getting > locked a few seconds so the VM keeps running during

Re: [Gluster-users] Questions about healing

>That's clear but if you have a cluster of 3, with replica 3, if you loose >a node, you have to heal the whole VM image as shards are not >distributed,A as there aren't nodes to distribute to. > >All nodes has all shards in my case. > >Sharding would be useful in very large

Re: [Gluster-users] Questions about healing

>Which is the OS reaction to a locked storage?A It's transparent or could >lead to FS issue? >What would happen if healing starts in the middle of a write, for example >when MySQL flush to disks? In my experience the OS can't notice that, actually. The access to the disk won't

Re: [Gluster-users] Questions about healing

Il 21 mag 2016 08:38, "Kevin Lemonnier" ha scritto: > Yeah, but healing a few MB shard takes a few second, so the VM is frozen for a very small > amount of time. Without sharding, the VM is frozen as long as the whole disk hasn't > been healed, which will take hours on big

Re: [Gluster-users] Questions about healing

>Anyway how is possible to keep VM up and running when healing is happening >on a shard? That part of disk image is not accessible and thus the VM >could have some issue on a filesystem. Yeah, but healing a few MB shard takes a few second, so the VM is frozen for a very small amount

Re: [Gluster-users] Questions about healing

Well it's not magic, there is an algorithm that is documented and it is trivial script the recreation of the file from the shards if gluster was truly unavailable: > > > #!/bin/bash > # > # quick and dirty reconstruct file from shards > # takes brick path and file name as arguments > # Copyright

Re: [Gluster-users] Questions about healing

Il 20 mag 2016 20:14, "Alastair Neil" ha scritto: > > I think you are confused about what sharding does. In a sharded replica 3 volume all the shards exist on all the replicas so there is no distribution. Might you be getting confused with erasure coding? The upshot of

Re: [Gluster-users] Questions about healing

I think you are confused about what sharding does. In a sharded replica 3 volume all the shards exist on all the replicas so there is no distribution. Might you be getting confused with erasure coding? The upshot of sharding is that if you have a failure, instead of healing multiple gigabyte

Re: [Gluster-users] Questions about healing

Il 18 mag 2016 19:31, "Kevin Lemonnier" ha scritto: > Seems like a non issue, you are planning in using replica right ? Yes but what if in case of a gluster bug? Replica protect against hardware failure but also software could fail. What if sharding algorithm would be

Re: [Gluster-users] Questions about healing

On Wed, May 18, 2016 at 06:54:57PM +0200, Gandalf Corvotempesta wrote: > Il 18/05/2016 13:55, Kevin Lemonnier ha scritto: > > Yes, that's why you need to use sharding. With sharding, the heal is > > much quicker and the whole VM isn't freezed during the heal, only the > > shard being healed. I'm

Re: [Gluster-users] Questions about healing

Il 18/05/2016 13:55, Kevin Lemonnier ha scritto: Yes, that's why you need to use sharding. With sharding, the heal is much quicker and the whole VM isn't freezed during the heal, only the shard being healed. I'm testing that right now myself and that's almost invisible for the VM using 3.7.11.

Re: [Gluster-users] Questions about healing

On Wed, May 18, 2016 at 01:39:58PM +0200, Gandalf Corvotempesta wrote: > Ciao, > i'm planning a new infrastructure. I have some questions about > healing to better optimize performances in case of brick failure. > > Let's assume this environment: > > 3 supermicro servers, replica 3, with 12 SATA

[Gluster-users] Questions about healing

Ciao, i'm planning a new infrastructure. I have some questions about healing to better optimize performances in case of brick failure. Let's assume this environment: 3 supermicro servers, replica 3, with 12 SATA disks each. each servers has 2 bricks in RAID-6 (software or hardware, i don't