Is it me or is FreeBSD slower on Xen than Linux?

[rainer at ultra-secure.de]

Am 2016-08-16 13:08, schrieb Roger Pau Monné:

> And FreeBSD on bare metal is equally fast as Linux then? (ie: the 
> slowdown
> is only noticeable when running FreeBSD on Xen)


Yes.

I should clarify a bit more.
The task involves 12000 (simple) MySQL-Queries, where the script 
basically selects the numbers 1...4000 from a table (it's stupid, I 
know) and then proceeds to run a for i in ... loop 4000 times which 
consists of three other sql-queries, where the WHERE-clause is 
constrained by the value from above.

We've now found that indeed MariaDB is much faster on Xen-Linux than 
Xen-FreeBSD.

The tables all use innodb and the DB is sitting on UFS (in the 
FreeBSD-on-Xen case, the FreeBSD-on-bare-metal has ZFS).
Linux is using ext4.

Could this really be an UFS vs. ext4 thing?

I assume that optimizations in MariaDB 10.1 lead to less disk-activity.


I haven't had a chance to try MariaDB on Linux on bare-metal (we don't 
really have one where I could test this ATM).


> If you can provide me with some way to synthesize this workload that 
> doesn't
> involve setting up the full stack plus your app I can try to reproduce 
> it
> locally and analyze it in order to find the bottlenecks.


It's a bit of a pain to setup (mariadb, php-fpm, nginx). Also, you need 
some files from another framework (apparently)....