Re: [MooseFS-Users] high packet travel time

[Aleksander W. <ale...@mo...>]

Hi,

According to your system log, we can notice two different problems:

1.) First problem is "high packet travel".

I would like to inform you that since version 3.0.x MooseFS has new time
calculation method.
Master is able to calculate "real" packet time travel between MooseFS
Master and clients.
In a glance. Echo packet is send  through TCP and goes to master queue.
So time of operation is a sum of time, that Master spends on ECHO reply
and packet travel time.
Time difference larger than 10ms can influence on all operations
performance.

Information about "high packet travel time" can mean, that:
- Network traffic is huge,
- Router is not able to handle large number of packets traffic,
- Master is busy - CPU utilisation is close to 100%,
- Some interfaces have TX/RX errors.

If you notice this entry in your system log rarely you can ignore it,
but if you see it often, consider to do some investigation.
Also please check if you network configuration is error-free.
Always good idea is do perform some simple ping test to see if your
latency is really small.

By the way. Your MooseFS master is hardware or virtual machine?


2.) Second problem i "time desync".

Information about time de-synchronization between client and master
means that local data is different on master and client.
So please check if you have enabled some ntp time synchronization on all
MooseFS components.

I'm looking forward to hearing from you.

Best regards,
Aleksander Wieliczko
Technical Support Engineer
MooseFS.com <moosefs.com>