backup in directadmin without caching

M

monaliza

Verified User
Joined
Dec 2, 2014
Messages
9
hi
when i make a backup in directadmin or scp a large file
The cache ram is starting to fill up
Is this normal?
How to make a backup without caching?

My config
ubuntu 20.04
litespeed
Directadmin
opcache

Thanks a lot
 
Under caching you mean disk caching? Or cache memory? Or the way directadmin collects all files under one location before compressing them? Kindly clarify.
 
Memory Cache
on system-info
 

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If this is the case, you dig it a wrong way. Even if Memory Cache is used here, then it has much more IO speed then storage drives of a server.
 
Do you want to say that sites open from your server slower when backups are running? And you think memory cache is the culprit?
 
Not during backup
I guess it slows down because the RAM cache is busy
And backup cache replaces the pages cache, so the pages load slower
isn't it?
 
I guest, you have many domain in your server and while backup process starting, Disk IO will become slowly.

I think, you need to use "ionice" on the backup process.

#directadmin.conf
Code: 
ionice_string=/usr/bin/ionice -c2 -n7

and restart directadmin
 
No
I have only three accounts with about 200 gigs of data
I use Moodle and Joomla software
And data(pages) caching is very important
no Backup caching
 
monaliza said:
And data(pages) caching is very important
no Backup caching
Click to expand...
Pages cache will always be rebuild after a restore, so do you mean you don't want to backup the caching folders?

If not, you can create a file called .backup_exclude_paths in the /home/user folder and add in there what is to be skipped.
This must be relative to that /home/user folder for example, if you want the skip /home/user/domains/mydomain.com/public_html_cache from the backup, then in that .backup_exclude_paths folder, add it like this
domains/mydomain,com/public_html/cache
and don't use a starting forward slash, just as in this example.

Ofcourse use the correct domain name and path to what you want to skip. You can also skip files this way.
 
Richard G said:
Pages cache will always be rebuild after a restore, so do you mean you don't want to backup the caching folders?
Click to expand...

From what I understood, it is about RAM (memory): The user wants CACHED memory to keep websites data. But the CACHED memory gets reset when backups are running. And it takes time to CACHED memory to get populated with data from sites again.
 
In fact, I am looking for a way that the RAM cache is not involved during Fullbackup.

my reasoning:
so that the backup cache does not replace the pages cache
and has to be rebuild again pages cache
which may have a negative effect on performance

Is my reasoning correct?
 
Then you should create backups outside your server, something like using remote mounting. And even in this case I really doubt you will hit the goal.
 
Uhm... not allowing the backups to use ram (os determines mostly how this is manged) would probably bring your server down pretty fast as it wouldn't be able to cache (millions?) of files for the backups. It would also increase the IO with A LOT, which you would notice pretty fast if the sites need IO to get te pages. Or am I wrong?
But the 'cache' ram is the first to get freed when the os thinks there is better use for it. Why don't you get a cheap vps and have that rsync your server? That will give you all the ram you have (minus a few gb).
On the other hand... if you can use things like memcached, redis etc... you could probably use that to keep the memory occupied so it won't get assigned to cache.
 
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