Does CloudStack support PXC?

[li jerry <di...@hotmail.com>]

Hi, dear cloudstack users
I see that PXC (percona xtradb cluster) has excellent functions.

But it has the following limitations:
Only InnoDB storage engine is supported
Lock / unlock tables is not supported
Lock function (get) is not supported_ LOCK(), RELEASE_ LOCK()


Does cloudstack use the above functions?
Can I convert the MySQL used by cloudstack to PXC?

Has anyone used PXC in cloudstack?

-Jerry

Re: Does CloudStack support PXC?

[Ivan Kudryavtsev <iv...@bw-sw.com>]

Hi, Cloudstack heavily relies on lock/unlock functionality.
Galera cluster is fine, but as Andrija says, there is a single read/write
node for all cs management must be used.

чт, 12 нояб. 2020 г., 20:31 Andrija Panic <an...@gmail.com>:

> As long as you use a single node for writes and reads - yes.
> Some users have used mysql proxy to send writes to node1, and reads to
> node1/2/3 and eventually, I believe they had some issues (but that was not
> confirmed to be the root cause)
>
> You can also use haproxy in front of percona cluster (alwaus a single node,
> and 2 "backup" nodes), so failover is seamless (like in case of mysql
> proxy), but we warned that IN PAST there was some stupidly long (not
> closed) mysql sessions/connection that would cause ACS to throw exception
> during i.e. long lasting volume snapshots (DB Connection was keept open
> during the backing up of the snap to Sec Stor, and at some time haproxy
> would close the connection adn ACS would crash) - but this was fixed in 4,9
> or so - so should be a safe bet these days.
>
> Make sure to test extensively
> Nothing to convert really, dump the DBs properly, import into PXC.
>
> Best,
>
> On Wed, 11 Nov 2020 at 14:52, li jerry <di...@hotmail.com> wrote:
>
> > Hi, dear cloudstack users
> > I see that PXC (percona xtradb cluster) has excellent functions.
> >
> > But it has the following limitations:
> > Only InnoDB storage engine is supported
> > Lock / unlock tables is not supported
> > Lock function (get) is not supported_ LOCK(), RELEASE_ LOCK()
> >
> >
> > Does cloudstack use the above functions?
> > Can I convert the MySQL used by cloudstack to PXC?
> >
> > Has anyone used PXC in cloudstack?
> >
> > -Jerry
> >
> >
>
> --
>
> Andrija Panić
>

Re: Does CloudStack support PXC?

[Andrija Panic <an...@gmail.com>]

As long as you use a single node for writes and reads - yes.
Some users have used mysql proxy to send writes to node1, and reads to
node1/2/3 and eventually, I believe they had some issues (but that was not
confirmed to be the root cause)

You can also use haproxy in front of percona cluster (alwaus a single node,
and 2 "backup" nodes), so failover is seamless (like in case of mysql
proxy), but we warned that IN PAST there was some stupidly long (not
closed) mysql sessions/connection that would cause ACS to throw exception
during i.e. long lasting volume snapshots (DB Connection was keept open
during the backing up of the snap to Sec Stor, and at some time haproxy
would close the connection adn ACS would crash) - but this was fixed in 4,9
or so - so should be a safe bet these days.

Make sure to test extensively
Nothing to convert really, dump the DBs properly, import into PXC.

Best,

On Wed, 11 Nov 2020 at 14:52, li jerry <di...@hotmail.com> wrote:

> Hi, dear cloudstack users
> I see that PXC (percona xtradb cluster) has excellent functions.
>
> But it has the following limitations:
> Only InnoDB storage engine is supported
> Lock / unlock tables is not supported
> Lock function (get) is not supported_ LOCK(), RELEASE_ LOCK()
>
>
> Does cloudstack use the above functions?
> Can I convert the MySQL used by cloudstack to PXC?
>
> Has anyone used PXC in cloudstack?
>
> -Jerry
>
>

-- 

Andrija Panić