Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1209297

Re: [PATCH] drbd: Support zeroout device instead of initial full sync

From Lars Ellenberg <lars.ellenberg@linbit.com>
Newsgroups linux.kernel
Subject Re: [PATCH] drbd: Support zeroout device instead of initial full sync
Date 2015-08-18 17:20 +0200
Message-ID <pYQQa-1B4-5@gated-at.bofh.it> (permalink)
References <pShV8-5Ml-11@gated-at.bofh.it> <pUqhA-5Mv-13@gated-at.bofh.it> <pUqhA-5Mv-17@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Thu, Aug 06, 2015 at 06:04:22PM +0800, Nick Wang wrote:
> Patch set for zeroing out device on both side
> instead of initial full sync. Useful for high
> latency network environment.
> 
> Implement --zeroout-devices and --discard-devices
> for new-current-uuid

I still think this does not belong into the kernel at all.
I may not yet have properly explained why.

This is a lot of stuff to add to the DRBD module,
introducing write protocol incompatibility/protocol version bump.

For no good reason.

you want to create a new drbd,
and want to make sure the backing devices are discarded:

# blkdiscard /dev/backing
and then proceed with
# drbdadm create-md ...
as normal, and skip the initial sync as documented.

You want to grow an existing drbd,
you have to grow the backend first, anyways,
you can then (if necessary)
# blkdiscard --offset $o --length $l /dev/backing,
# drbdadm resize ... --assume-clean ...

No need to touch either the DRBD module, or the DRBD utils at all.
All there already.

	Lars Ellenberg

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread


Thread

[PATCH v3 0/1] Zeroout/discard devices instead of initial full sync Nick Wang <nwang@suse.com> - 2015-08-06 12:10 +0200
  [PATCH] drbd: Support zeroout device instead of initial full sync Nick Wang <nwang@suse.com> - 2015-08-06 12:10 +0200
    Re: [PATCH] drbd: Support zeroout device instead of initial full sync Lars Ellenberg <lars.ellenberg@linbit.com> - 2015-08-18 17:20 +0200

csiph-web