CPU
- Lancer un sar 1 10 pour avoir une vue globale de la machine :
root@server1104092:~# sar 1 10 Linux 2.6.9-67.ELsmp (server1104092) 11/12/08 14:57:54 CPU %user %nice %system %iowait %idle 14:57:55 all 11.60 0.00 4.49 25.94 57.98 14:57:56 all 10.88 0.00 3.75 25.00 60.38 14:57:57 all 10.59 0.00 3.86 24.41 61.15 14:57:58 all 10.76 0.00 4.13 24.66 60.45 14:57:59 all 11.36 0.00 4.99 24.22 59.43 14:58:00 all 11.51 0.00 3.25 27.91 57.32
- On peut utiliser top :
top - 15:07:42 up 10 days, 7:32, 20 users, load average: 1.87, 2.72, 2.58 Tasks: 448 total, 1 running, 447 sleeping, 0 stopped, 0 zombie Cpu(s): 7.6% us, 0.9% sy, 0.0% ni, 87.3% id, 3.1% wa, 0.1% hi, 0.9% si Mem: 65747848k total, 65217884k used, 529964k free, 168860k buffers Swap: 65535992k total, 976k used, 65535016k free, 62379852k cached PID USER PR NI %CPU TIME+ %MEM VIRT RES SHR S COMMAND 32368 root 16 0 54 37:38.27 0.0 20456 5028 3604 S dsmc 17209 sybase 16 0 5 252:52.99 7.3 7327m 4.6g 4.6g S RPO_dataserver 17211 sybase 16 0 4 305:02.35 7.5 7327m 4.7g 4.7g S RPO_dataserver 26930 root 16 0 1 20:23.75 0.0 2900 1828 520 S cmaperfd 14326 sybase 15 0 1 394:40.93 9.3 7327m 5.8g 5.8g S IRD_dataserver 18525 sybase 15 0 1 232:11.65 5.4 7331m 3.4g 3.4g S RPS_dataserver 30714 root 16 0 1 0:00.07 0.0 6424 1428 848 R top 14323 sybase 15 0 0 419:17.35 9.3 7327m 5.8g 5.8g S IRD_dataserver 15498 sybase 15 0 0 522:40.79 9.1 7578m 5.7g 5.7g S IRS_dataserver 16354 sybase 15 0 0 291:18.70 11.0 7337m 6.9g 6.9g S RPO_dataserver 17207 sybase 15 0 0 346:40.57 7.5 7327m 4.7g 4.7g S RPO_dataserver 18003 sybase 15 0 0 266:00.77 11.0 7341m 6.9g 6.9g S RPS_dataserver 22149 root 15 0 0 3:32.06 0.0 0 0 0 S kjournald 25904 root 15 0 0 22:04.93 0.0 0 0 0 S kpanfs_thpool 25905 root 15 0 0 22:03.25 0.0 0 0 0 S kpanfs_thpool
→ SHIFT + F pour changer la colonne de tri, etc. h pour l'aide.
Top process
ps -eo pcpu,pid,user,args | sort -k 1 -r | head -10 ps -eo pcpu,pid,user,args | sort -r -k1 | less
Mémoire
- Vérifier la mémoire avec un sar -r 1 10 et free -m :
root@server1104092:~# sar -r 1 10 Linux 2.6.9-67.ELsmp (server1104092) 11/12/08 15:05:25 kbmemfree kbmemused %memused kbbuffers kbcached kbswpfree kbswpused %swpused kbswpcad 15:05:26 488156 65259692 99.26 170472 62419380 65535016 976 0.00 0 15:05:27 479004 65268844 99.27 170488 62426708 65535016 976 0.00 0 15:05:28 471644 65276204 99.28 170504 62436008 65535016 976 0.00 0 15:05:29 463452 65284396 99.30 170512 62444228 65535016 976 0.00 0 15:05:30 454292 65293556 99.31 170540 62453448 65535016 976 0.00 0 15:05:31 445596 65302252 99.32 170552 62462344 65535016 976 0.00 0
root@server1104092:~# free -m
total used free shared buffers cached
Mem: 64206 63597 609 0 165 60824
-/+ buffers/cache: 2607 61599
Swap: 63999 0 63999
→ ici on a 2607 Mo de ram utilisée et 60824 Mo de cache (utilisable par le kernel en cas de besoin). La valeur 63597 Mo correspond à la mémoire allouée, 61599 correspond à la mémoire disponible.
- vmstat -s affiche les infos détaillées sur la mémoire :
root@server2311829:/# vmstat -s
24665472 total memory
15389220 used memory
14490508 active memory
136844 inactive memory
9276252 free memory
768868 buffer memory
10595768 swap cache
25165816 total swap
0 used swap
25165816 free swap
12203574 non-nice user cpu ticks
32747 nice user cpu ticks
141624951 system cpu ticks
4344770172 idle cpu ticks
579126 IO-wait cpu ticks
409728 IRQ cpu ticks
181938 softirq cpu ticks
9452723 pages paged in
690716466 pages paged out
0 pages swapped in
0 pages swapped out
1640151373 interrupts
765936041 CPU context switches
1223379772 boot time
314718391 forks
- un cat /proc/meminfo donne aussi des infos pertinentes (noyau 2.6 dans notre cas) :
root@parcl1104092:~# cat /proc/meminfo MemTotal: 65747848 kB MemFree: 4676348 kB Buffers: 155412 kB Cached: 58250332 kB SwapCached: 0 kB Active: 42665024 kB Inactive: 17041772 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 65747848 kB LowFree: 4676348 kB SwapTotal: 65535992 kB SwapFree: 65535016 kB Dirty: 3148 kB Writeback: 0 kB Mapped: 31220740 kB Slab: 789220 kB CommitLimit: 98409916 kB Committed_AS: 33127992 kB PageTables: 419756 kB VmallocTotal: 536870911 kB VmallocUsed: 51352 kB VmallocChunk: 536819195 kB HugePages_Total: 0 HugePages_Free: 0 Hugepagesize: 2048 kB
→ Buffers & Cached : cette mémoire peut-être utilisée par le kernel en cas de besoin, c'est la mémoire disponible (mais allouée)
→ Active : mémoire récemment utilisée qui ne sera pas utilisée par le kernel sauf en cas de besoin fort
→ Inactive : mémoire utilisée pouvant être utilisée par le kernel si besoin
→ Dirty : datas non flushées sur le disque (ou en cours)
→ D'autres infos ici.
- Un petit vmstat 1 10 donne aussi des infos utiles :
root@server1104092:~# vmstat 1 10 procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 2 976 472404 165332 62007272 0 0 460 550 5 2 12 5 77 6 2 0 976 467988 165340 62012296 0 0 2208 236 16949 36775 15 12 66 8 5 0 976 463380 165360 62016900 0 0 2088 1705 9980 36940 16 9 70 5 3 0 976 457684 165364 62022064 0 0 2264 397 7457 44781 12 9 73 6 6 0 976 452564 165376 62027832 0 0 2260 275 6159 45565 20 10 66 4 1 3 976 447988 165376 62033068 0 0 2376 9536 7778 35145 15 10 68 7 3 1 976 440628 165384 62038772 0 0 2496 556 8299 71486 21 11 63 5 0 0 976 433684 165400 62045624 0 0 3108 696 5167 52533 10 9 74 6 0 1 976 427284 165400 62051948 0 0 2892 216 4757 45852 12 8 74 7 1 0 976 421468 165404 62056160 0 0 1620 609 6609 69289 11 8 75 6
Les champs so et si permettent de voir l'activité de swap. On peut voir la runqueue r et les process b qui attendent des I/O (réseau, disque) b, cf le man pour les autres infos (cs → context swicth, in → interrupts, etc).
Disque
- vmstat -d 1 1
root@server2311829:/# vmstat -d 1 1
disk- ------------reads------------ ------------writes----------- -----IO------
total merged sectors ms total merged sectors ms cur sec
ram0 0 0 0 0 0 0 0 0 0 0
ram1 0 0 0 0 0 0 0 0 0 0
ram2 0 0 0 0 0 0 0 0 0 0
ram3 0 0 0 0 0 0 0 0 0 0
ram4 0 0 0 0 0 0 0 0 0 0
ram5 0 0 0 0 0 0 0 0 0 0
ram6 0 0 0 0 0 0 0 0 0 0
ram7 0 0 0 0 0 0 0 0 0 0
ram8 0 0 0 0 0 0 0 0 0 0
ram9 0 0 0 0 0 0 0 0 0 0
ram10 0 0 0 0 0 0 0 0 0 0
ram11 0 0 0 0 0 0 0 0 0 0
ram12 0 0 0 0 0 0 0 0 0 0
ram13 0 0 0 0 0 0 0 0 0 0
ram14 0 0 0 0 0 0 0 0 0 0
ram15 0 0 0 0 0 0 0 0 0 0
hda 0 0 0 0 0 0 0 0 0 0
sda 194356 5945 4172146 137864 96031752 77260674 1380561782 51965656 0 6458
dm-0 11404 0 509890 13774 28497459 0 227979672 39823426 0 701
dm-1 13623 0 533730 13236 7019350 0 56154800 11378930 0 637
dm-2 2998 0 24154 844 109615714 0 876925712 7213939 0 3883
dm-3 2972 0 23770 1397 280989 0 2247912 3567093 0 42
dm-4 3373 0 78090 1367 2954396 0 23635168 5853703 0 166
dm-5 69064 0 2116530 67730 2682039 0 21456312 8221587 0 204
dm-6 5320 0 114218 7105 2974177 0 23793416 267554994 0 381
dm-7 2909 0 23272 621 0 0 0 0 0 0
dm-8 3222 0 25770 8636 7034863 0 56278904 2119759062 0 217
md0 0 0 0 0 0 0 0 0 0 0
loop0 0 0 0 0 0 0 0 0 0 0
loop1 0 0 0 0 0 0 0 0 0 0
loop2 0 0 0 0 0 0 0 0 0 0
loop3 0 0 0 0 0 0 0 0 0 0
loop4 0 0 0 0 0 0 0 0 0 0
loop5 0 0 0 0 0 0 0 0 0 0
loop6 0 0 0 0 0 0 0 0 0 0
loop7 0 0 0 0 0 0 0 0 0 0
dm-9 2235 0 17874 2412 474271 0 3794168 150902341 0 27
dm-10 3787 0 22986 1879 318459 0 654606 163241 0 9
dm-11 5240 0 34388 4321 197786 0 424060 493783 0 5
dm-12 5274 0 34456 4168 323270 0 675028 963431 0 5
dm-15 1721 0 13762 1684 5671213 0 45369704 8472081 0 458
dm-16 1708 0 13658 8814 469486 0 3755888 64149095 0 21
dm-17 1764 0 14106 3557 4370518 0 34964144 204951066 0 231
dm-14 3378 0 19768 1341 62748 0 138480 209068 0 2
dm-18 3784 0 22980 1701 45660 0 109008 60575 0 3
dm-19 807 0 6450 525 249030 0 1992240 6801428 0 4
dm-20 2868 0 19382 1516 25806 0 69300 1170260 0 1
→ Ici on voit l'activité de chaque device. Pour déterminer à quel LV correspond quel device dm-x voir ici.
- iostat -k -x 1 10
root@server2311828:/# iostat -k -x 1 1
Linux 2.6.9-67.ELsmp (parsl2311828) 12/11/2008
avg-cpu: %user %nice %sys %iowait %idle
1.09 0.00 18.40 0.11 80.40
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 62.30 0.05 106.47 0.92 585.84 0.46 292.92 5.51 0.01 0.13 0.05 0.58
dm-0 0.00 0.00 0.00 20.08 0.12 160.66 0.06 80.33 8.00 0.02 0.82 0.02 0.05
dm-1 0.00 0.00 0.00 1.95 0.10 15.56 0.05 7.78 8.04 0.00 0.67 0.05 0.01
dm-2 0.00 0.00 0.00 139.36 0.00 351.81 0.00 175.91 2.52 0.01 0.06 0.04 0.51
dm-3 0.00 0.00 0.00 0.03 0.00 0.24 0.00 0.12 8.00 0.00 0.26 0.05 0.00
dm-4 0.00 0.00 0.00 1.65 0.00 13.20 0.00 6.60 8.00 0.00 2.19 0.04 0.01
dm-5 0.00 0.00 0.01 0.65 0.41 5.22 0.21 2.61 8.44 0.00 1.87 0.06 0.00
dm-6 0.00 0.00 0.00 0.64 0.03 5.12 0.01 2.56 8.03 0.03 51.40 0.08 0.00
dm-7 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 8.00 0.00 0.34 0.21 0.00
dm-8 0.00 0.00 0.00 0.84 0.00 6.70 0.00 3.35 8.00 0.15 184.80 0.03 0.00
dm-9 0.00 0.00 0.00 0.20 0.01 1.60 0.00 0.80 8.01 0.04 205.42 0.04 0.00
dm-10 0.00 0.00 0.00 0.03 0.00 0.07 0.00 0.04 2.18 0.00 0.35 0.03 0.00
dm-11 0.00 0.00 0.00 0.05 0.01 0.10 0.00 0.05 2.20 0.00 0.41 0.03 0.00
dm-12 0.00 0.00 0.00 0.08 0.01 0.16 0.00 0.08 2.12 0.00 0.38 0.03 0.00
dm-15 0.00 0.00 0.00 1.67 0.06 13.35 0.03 6.67 8.02 0.00 0.29 0.08 0.01
dm-16 0.00 0.00 0.00 0.17 0.00 1.33 0.00 0.67 8.00 0.00 0.55 0.04 0.00
dm-17 0.00 0.00 0.00 1.18 0.03 9.44 0.02 4.72 8.00 0.13 108.44 0.07 0.01
dm-14 0.00 0.00 0.00 0.01 0.00 0.03 0.00 0.01 2.39 0.00 1.09 0.06 0.00
dm-18 0.00 0.00 0.00 0.01 0.00 0.02 0.00 0.01 2.73 0.00 0.40 0.10 0.00
dm-19 0.00 0.00 0.00 0.13 0.00 1.01 0.00 0.51 8.00 0.00 0.63 0.05 0.00
dm-20 0.00 0.00 0.00 0.02 0.01 0.05 0.00 0.03 2.34 0.00 0.57 0.04 0.00
→ Pour afficher les infos sur l'utilisation des disques
Réseau
- mii-tool et ethtool pour vérifier le statut des cartes :
root@server1104092:~# mii-tool eth0: 100 Mbit, full duplex, link ok eth1: no link eth2: 100 Mbit, full duplex, link ok eth3: negotiated, link ok eth4: 100 Mbit, full duplex, link ok eth5: negotiated, link ok eth6: 100 Mbit, full duplex, link ok eth7: negotiated, link ok
root@server1104092:~# ethtool eth7
Settings for eth7:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 1000baseT/Full
Advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: umbg
Wake-on: g
Current message level: 0x00000007 (7)
Link detected: yes
- netstat -taunpo|grep -c ESTA pour vérifier le nombre de connexions établies
Sémaphores
Pour voir la conf des sémaphores :
root@server9010504:/# cat /proc/sys/kernel/sem 1024 32000 100 606 SEMMSL - semaphores per ID SEMMNS - (SEMMNI*SEMMSL) max semaphores in system SEMOPM - max operations per semop call SEMMNI - max semaphore identifiers
Ca se modifie à chaud avec la commande :
echo "1024 32000 100 606" > /proc/sys/kernel/sem
Il ne faut pas oublier de modifier la ligne kernel.sem du fichier /etc/sysctl.conf pour la prise en compte aux prochains reboots :
root@server9010504:/# grep kernel.sem /etc/sysctl.conf kernel.sem = 1024 32000 100 606
On retrouve les infos aussi avec la commande ipcs :
root@server9010504:/# ipcs -s -l ------ Semaphore Limits -------- max number of arrays = 606 max semaphores per array = 1024 max semaphores system wide = 32000 max ops per semop call = 100 semaphore max value = 32767
Description
| Semaphore | Description | Minimum |
|---|---|---|
| SEMMSL | maximum number of semaphores per array | 128 |
| SEMMNS | maximum semaphores system-wide | |
| SEMOPM | maximum operations per semop call | |
| SEMMNI | maximum arrays |
Calcul des valeurs
Source 1)
- Calculate the minimum total semaphore requirements using the following formula:
sum (process parameters of all database instances on the system) + system and other application requirements
Set semmns (total semaphores systemwide) to this total.
Set semmsl (semaphores per set) to 256.
Set semmni (total semaphores sets) to semmns / semmsl rounded up to the nearest multiple of 1024.
The following formula can be used as a guide, although in practice, SEMMNS and SEMMNU can be much less than SEMMNI * SEMMSL because not every program in the system needs semaphores.
SEMMNS = SEMMNU = (SEMMNI * SEMMSL)