Buna seara
Ma confrunt de ceva vreme cu o problema.
Pe un server stabil , productie, cu 2xIntel(R) Xeon(R) CPU E5620 @ 2.40GHz si 32GB Ram avand ubuntu12.04 / 64 se adauga un controler cu 2 SSD -uri 1 TB raid 1 mirror pe care se va dori a se stoca tabele mysql. Creez partitia lvm de test .
root@hpserver:~# uname -a
Linux hpserver 3.2.0-70-generic #105-Ubuntu SMP Wed Sep 24 19:49:16 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
root@hpserver:~# hdparm -I /dev/sda | grep "TRIM"
* Data Set Management TRIM supported (limit unknown)
pvcreate /dev/sda
vgcreate VG-SSD /dev/sda
lvcreate -L 100G -n Partitie1_tmp_SSD VG-SSD
root@hpserver:~# mkfs.ext4 /dev/VG-SSD/Partitie1_tmp_SSD
mke2fs 1.42 (29-Nov-2011)
Discarding device blocks: done
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
6553600 inodes, 26214400 blocks
1310720 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
800 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
Dupa dupa ce fac mount , pot folosi systemul de fisiere de pe SSD .
root@hpserver:~# mount /dev/VG-SSD/Partitie1_tmp_SSD /mnt/SSD_tmp/
root@hpserver:~# mkdir /mnt/SSD_tmp/test_ssd
root@hpserver:~# ls -la /mnt/SSD_tmp/
total 28
drwxr-xr-x 4 root root 4096 Jan 12 18:50 .
drwxr-xr-x 6 root root 4096 Jan 12 14:55 ..
drwx------ 2 root root 16384 Jan 12 18:41 lost+found
drwxr-xr-x 2 root root 4096 Jan 12 18:50 test_ssd
Uneori imediat , alteori mai tarziu, cand execut trim si umount / mount de cateva ori apare un fenomen, sistemul de fisiere se corupe , nu se mai vede nici macar folderul de lost+found.
df -h imi arata partitia montata si faptul ca am date pe ea, insa nu mai pot accesa acele datele si nu mai pot scrie nimic
root@hpserver:~# ls -la /mnt/SSD_tmp/
total 0
root@hpserver:~# mkdir /mnt/SSD_tmp/test_ssd3
mkdir: cannot create directory `/mnt/SSD_tmp/test_ssd3': Input/output error
root@hpserver:~# fstrim -v /mnt/SSD_tmp
/mnt/SSD_tmp: 105492676608 bytes were trimmed
root@hpserver:~# ls -la /mnt/SSD_tmp/
total 0
root@hpserver:~# umount /mnt/SSD_tmp/
root@hpserver:~# mount /dev/VG-SSD/Partitie1_tmp_SSD /mnt/SSD_tmp/
root@hpserver:~# ls -la /mnt/SSD_tmp/
total 0
root@hpserver:~# mkdir /mnt/SSD_tmp/test_ssd3
mkdir: cannot create directory `/mnt/SSD_tmp/test_ssd3': Input/output error
root@hpserver:~# fstrim -v /mnt/SSD_tmp
/mnt/SSD_tmp: 105492676608 bytes were trimmed
root@hpserver:~# fstrim -v /mnt/SSD_tmp
/mnt/SSD_tmp: 0 bytes were trimmed
root@hpserver:~# fstrim -v /mnt/SSD_tmp
/mnt/SSD_tmp: 0 bytes were trimmed
root@hpserver:~# mkdir /mnt/SSD_tmp/test_ssd3
mkdir: cannot create directory `/mnt/SSD_tmp/test_ssd3': Input/output error
root@hpserver:~# fstrim -v /mnt/SSD_tmp
/mnt/SSD_tmp: 0 bytes were trimmed
root@hpserver:~# umount /mnt/SSD_tmp/
Nu am idee ce produce acest fenomen , sa fie problema la SSD , sau soft cumva si e legat de trim. Am folosit intens si copiat fara probleme cantitati destul de mari de date , tabele actuale mysql sunt de 30 Gb si urmeaza sa creasca , in mod normal echipamentul ramane pornit tot timpul , insa am avut curiozitatea sa vad ce se intampla dupa mai multe mount / umount / trim si nu mi-a placut deloc sa nu pot accesa datele. Sistemul actual de operare nu se poate schimba momentan. Curios este ca am incercat si cu mai multe partitii lvm, prima partitie in general ramane in stare de functionare , in timp ce restul se corup
Va multumesc pentru atentie , astept cu interes orice idee, sugestie , solutie !