Re: Bottlenecks with large number of relation segment files

On 08/05/2013 10:42 AM, John R Pierce wrote:
> On 8/5/2013 1:01 AM, KONDO Mitsumasa wrote:
>> When we open file, ext3 or ext4 file system seems to sequential search
>> inode for opening file in file directory.
>
> no, ext3/4 uses H-tree structures to search directories over 1 block
> long quite efficiently.

And the Linux dentry cache is rather aggressive, so most of the time,
only the in-memory hash table will be consulted.  (The dentry cache only
gets flushed on severe memory pressure.)

--
Florian Weimer / Red Hat Product Security Team