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To: Philipp Reisner <philipp.reisner@linbit.com>, Jens Axboe <axboe@fb.com>,
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From: Bart Van Assche <bart.vanassche@sandisk.com>
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Date: Mon, 25 Apr 2016 08:35:26 -0700
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Subject: Re: [Drbd-dev] [PATCH 05/30] drbd: Introduce new disk config option
 rs-discard-granularity
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On 04/25/2016 05:10 AM, Philipp Reisner wrote:
> As long as the value is 0 the feature is disabled. With setting
> it to a positive value, DRBD limits and aligns its resync requests
> to the rs-discard-granularity setting. If the sync source detects
> all zeros in such a block, the resync target discards the range
> on disk.

Hello Phil,

Can you explain why rs-discard-granularity is configurable instead of 
e.g. setting it to the least common multiple of the discard 
granularities of the underlying block devices at both sides?

Thanks,

Bart.