I/O pattern of smbd / optimization of disk subsystem

[Heiner Lesaar]

Dear list,

I am keen to learn more about the characteristics on how smbd accesses the disks in terms of request sizes. Does this depend on some of the smb.conf parameters (max xmit etc.) or on the negotiated protocol with the smb client?

Can someone give me a hint on how to find out what the characteristic in my usecase would be? I read about blktrace and collectl as some of the suggested tools. Usage is mainly multiple, slow but big streaming reads and writes. 

My goal is to optimize the disk subsystem config (multiple raid5 sets)  to get the best performance from the disks without suffering from side-effects like read/modify/write penalties when the data isn't written in matching allocation sizes to hit the "full stripe" of the disks. Same for read processes obviously.


Thanks in advance for any input on this!

Heiner