Hi!
I've also reproduced this issue on this kernel
Linux desktop 4.10.0-28-generic #32~16.04.2-Ubuntu SMP Thu Jul 20
10:19:48 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
====================
Each one second, my program reads /sys/block/$DEVICE/stat.
It substracts previously saved values, then saves current values, so I
know the hdd activity.
But sometimes (once in 7 days) I've got too big values for sda
(between last and current ones) (5GB/second).
sudo lshw -class disk
*-disk
description: ATA Disk
product: SPCC Solid State
physical id: 0.0.0
bus info: scsi@2:0.0.0
logical name: /dev/sda
version: 08.2
serial: EB84075517B200427436
size: 111GiB (120GB)
capabilities: partitioned partitioned:dos
configuration: ansiversion=5 logicalsectorsize=512
sectorsize=512 signature=d01f3b8e
Also I've written the script for monitoring the statistics
#!/bin/bash
while (true) do
str=`date`" $(cat /sys/block/sda/stat)"
echo $str >> log.txt
sleep 10;
done
And got this values
Fr Jul 28 07:39:38 MSK 2017 2368466 475339 105223134 1362848 5753154
7692148 661424840 31319540 0 4790052 32687100
Fr Jul 28 07:39:48 MSK 2017 2368466 475339 105223134 1362848 5753170
7692160 661425104 31319548 0 4790060 32687108
Fr Jul 28 07:39:58 MSK 2017 2368466 475339 105223134 1362848 5753174
7692162 661425152 31319556 0 4790068 32687116
Fr Jul 28 07:40:08 MSK 2017 2369133 475339 105228750 1363380 5771079
7694395 706209560 31324696 0 4795572 32692780
Fr Jul 28 07:40:18 MSK 2017 2369133 475339 105228750 1363380 5771087
7694431 706209960 31324708 0 4795584 32692792
Fr Jul 28 07:40:28 MSK 2017 2369133 475339 105228750 1363380 5771091
7694433 706210008 31324716 0 4795592 32692800
Fr Jul 28 07:40:38 MSK 2017 2369133 475339 105228750 1363380 5771244
7694714 706213528 31325052 0 4795604 32693136
You can see that the difference (3,4 lines) is very big between
706209560 and 661425152, my ssd can read/write 250 Mb/sec, but not 5
Gb/sec.
--
Best regards,
Sergey Borisov
