Re: Poor ext4 performance questions

[Chris Murphy]

On Nov 10, 2014, at 11:26 PM, George R Goffe <grgoffe(a)yahoo.com&gt; wrote:

>  Hi,
>  
>  I have some large ext4 filesystems with large numbers of files in them and performance
> really sucks. After inactivity, a simple ls takes minutes to complete. I'm pretty sure
> the drive is now powering itself down due to this inactivity.
>  
>  
>  Are there tuning parameters that I could alter that would keep more of the filesystem
> meta data in memory? It looks like the data slowly migrates back to disk and as a result,
> takes minutes to fill back up enough to respond.
>  
>  Regards and THANKS for your help and your time, 
It could be fragmentation or it could be non-optimal directory structure. When was the
last fsck -f performed? It will optimize directories as needed, but can be forced with -D
but I’d ask on the ext4 list before using it. And e4defrag -c can be used to get a
fragmentation score, which can be run on a file or a directory.

http://vger.kernel.org/vger-lists.html#linux-ext4


Chris Murphy