[CentOS] Re: rsync and swapping

[Toby Bluhm]

Scott Silva wrote:
> on 1/30/2008 5:24 AM Jerry Geis spake the following:
>> hi all,
>>
>> I use rsync to copy/backup ALL my stuff to another disk.
>>
>> When I run this seems like my machine (4 GIG ram centos 5.1)
>> now begins to swap out more programs. Is there a way to reduce
>> that swapping? I am running with echo 1 > /proc/sys/vm/swappiness
>>
>> I simply mount /dev/sdc1 /mnt/backup; mkdir /mnt/backup/month.day.year
>> then rsync -a /home /mnt/backup/mon.day.year
>>
>> This is approximately 102G of data.
>>
>> Thanks for any suggestions.
>>
>> Jerry
> Rsync's main benefit is on backups of changed files. dumping to a new 
> destination every time makes rsync less efficient than just about 
> every other option.
> Now if you made the new directory, and hardlinked the old stuff to the 
> new directory, then rsync would shine.
>

I did the rsync hard link for a while. After 30+ hardlinks to each file 
built up, filesystem operations slowed down - not in a killer way, but I 
did notice it. I think it's better to just use --backup and write the 
previous version to a new dir with  --backup-dir=`date +%F` or some such 
scheme. You don't see the backups represented as a whole directory 
structure, but it's less messy.


-- 
Toby Bluhm
Alltech Medical Systems America, Inc.
30825 Aurora Road Suite 100
Solon Ohio 44139
440-424-2240