AnsweredAssumed Answered

SATA read speed gets worse in linux 3.14.52

Question asked by richardhu on Mar 17, 2016
Latest reply on Mar 18, 2016 by richardhu

Hello, all:

 

I test SATA performace on our custom board with intel SSD and figure out performance difference in kernel version.

 

My SSD is INTEL SSDSA2CT040G3.

The benchmark under windows 7 64 bit with CrystalDiskMark 5.1.2:

 

The test commad i use on target board:

echo performance >  /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Write test:

echo 3 > /proc/sys/vm/drop_caches

dd if=/dev/zero of=tempfile bs=1M count=1024 conv=fsync

 

Read test:

echo 3 > /proc/sys/vm/drop_caches

dd if=tempfile of=/dev/null bs=1M count=1024

 

Test Result:

(Rootfs is buildroot)

 

linux 3.14.52:

Write:

1073741824 bytes (1.0GB) copied, 26.856296 seconds, 38.1MB/s

Read:

1073741824 bytes (1.0GB) copied, 13.097736 seconds, 78.2MB/s

 

linux 3.10.53:

Write:

1073741824 bytes (1.0GB) copied, 28.990223 seconds, 35.3MB/s

Read:

1073741824 bytes (1.0GB) copied, 8.182314 seconds, 125.1MB/s

 

linux 3.0.35:

Write:

1073741824 bytes (1.0GB) copied, 36.756555 seconds, 27.9MB/s

Read:

1073741824 bytes (1.0GB) copied, 10.264888 seconds, 99.8MB/s

 

As you see, the read speed is 30% worse in linux 3.14.52 then linux 3.10.53.

 

Any idea ?

 

BR,

 

Richard

Outcomes