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Slow read and write speeds

I installed ceph but read speed is only 200mb / s. Can you tell me the reason

Can you give more info on what hardware you are using and how you are measuring the speed.

Hello,

Hardware includes:

4 osd :

OS: 200GB SAS HDD

Journal: 120GB SSD
OSD DISK: 2TB x04

on a server

5 mon

200GB hdd

ISCSI and Backend runing a 1 sw 10GB

I checked on the client software is read only 200mb / s
Checking on ceph, the write speed is 800mb / s

I checked on the client software is read only 200mb / s
Checking on ceph, the write speed is 800mb / s

My question was/is how do you check this ? please give more detail.

5 mon

How do you have 5 mon ? are you running PetaSAN ? What version ?

ISCSI and Backend runing a 1 sw 10GB

What do you mean 1 sw

How do you have 5 mon ? are you running PetaSAN ? What version ?\

I Running petasan version 2.0

What do you mean 1 sw

ISCSI and Backend runing a 1 switch 10GB

My question was/is how do you check this ? please give more detail.

I connected petasan to esxi and installed a win7 machine to test the write speed is 200mb / s

I benchmarked to achieve a record speed of 700mb / s

 

 

The installation of Win 7 is a single threaded io stream, if you run several concurrent installs on different vms /esxs at the same time you will get higher total value. Similarly on the benchmark tests, you will get higher values with many threads and low value in case of 1 thread. Also the throughput benchmark uses standard 4M block sizes, the Win 7 install most probably uses a smaller block size so it will be lower.

Last for bluestore to get the best performance  we recommend all flash drives, if you use hdd you should get a controller with write back cache.