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July 2014

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Subject:
Re: How do you speed up rsync?
From:
Steven Haigh <[log in to unmask]>
Reply To:
Steven Haigh <[log in to unmask]>
Date:
Sat, 12 Jul 2014 15:56:54 +1000
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On 12/07/2014 3:49 PM, ToddAndMargo wrote:
> On 07/11/2014 10:44 PM, Steven Haigh wrote:
>> On 12/07/2014 3:24 PM, ToddAndMargo wrote:
>>> On 07/11/2014 01:49 PM, Patrick J. LoPresti wrote:
>>>> On Fri, Jul 11, 2014 at 1:40 PM, Patrick J. LoPresti
>>>> <[log in to unmask]> wrote:
>>>>>
>>>>> Try giving the "--size-only" option to rsync.
>>>>
>>>> Better yet, try "--modify-window=1". From the rsync man page:
>>>>
>>>> --modify-window
>>>>                 When  comparing  two  timestamps, rsync treats the
>>>> timestamps as
>>>>                 being equal if they differ by no  more  than  the
>>>> modify-window
>>>>                 value.   This  is  normally  0 (for an exact match),
>>>> but you may
>>>>                 find it useful to set this to a larger value in some
>>>> situations.
>>>>                 In  particular,  when  transferring to or from an MS
>>>> Windows FAT
>>>>                 filesystem (which represents times with a 2-second
>>>> resolution),
>>>>                 --modify-window=1 is useful (allowing times to differ
>>>> by up to 1
>>>>                 second).
>>>>
>>>>
>>>>    - Pat
>>>>
>>>
>>> Hi Pat,
>>>
>>> --modify-window=1
>>>        3 hr - 9 sec
>>>
>>> --modify-window=10
>>>        3 hr - 8 sec
>>>
>>> Rat!  I really though this sounded right
>>>
>>>
>>> I did notice that the bugger the file (with no changes)
>>> the longer it took.  So, I think they are still doing
>>> check sums.
>>>
>>> Any way to turn of the check sum testing?
>>
>> Now you're starting to get off task... How can you sync something if you
>> don't know if it matches? Sure, you can only go off timestamps
> 
> How would I do size and time stamp?
> 
> Virtually everything I modify will either be a different size
> and/or get a new time stamp.  I can not think of a reason
> why, in this instance, I'd need to do a check sum.

Then you don't want to use rsync - as you're not syncing. rsync will
also checksum data AFTER copying to verify the copy was successful.

If you don't care about the rest, try the normal cp:
	cp -apu /path/to/source /path/to/destination

-- 
Steven Haigh

Email: [log in to unmask]
Web: http://www.crc.id.au
Phone: (03) 9001 6090 - 0412 935 897
Fax: (03) 8338 0299

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