Di recente abbiamo notato che le nostre query sul database hanno impiegato molto più tempo del solito per essere eseguite. Dopo alcune indagini, sembra che stiamo ricevendo letture del disco molto lente.
In passato abbiamo riscontrato un problema simile causato dal controller RAID che avviava un ciclo di riapprendimento sulla BBU e passa al write-through. Questa volta non sembra che sia così.
Ho corso bonnie++alcune volte nel corso di un paio di giorni. Ecco i risultati:
Le letture 22-82 M / s sembrano piuttosto spaventose. In esecuzione ddcontro il dispositivo non elaborato per alcuni minuti, è possibile visualizzare letture comprese tra 15,8 MB / sa 225 MB / s (vedere l'aggiornamento di seguito). iotopnon indica altri processi in competizione per IO, quindi non sono sicuro del perché la velocità di lettura sia così variabile.
La scheda raid è un MegaRAID SAS 9280 con 12 unità SAS (15k, 300GB) in RAID10 con un filesystem XFS (sistema operativo su due SSD configurati in RAID1). Non vedo alcun avviso SMART e l'array non sembra essere degradato.
Ho anche corso xfs_checke sembra che non ci siano problemi di coerenza XFS.
Quali dovrebbero essere i prossimi passi investigativi qui?
Specifiche del server
Ubuntu 12.04.5 LTS
128GB RAM
Intel(R) Xeon(R) CPU E5-2643 0 @ 3.30GHz
Uscita di xfs_repair -n:
Phase 1 - find and verify superblock...
Phase 2 - using internal log
- scan filesystem freespace and inode maps...
- found root inode chunk
Phase 3 - for each AG...
- scan (but don't clear) agi unlinked lists...
- process known inodes and perform inode discovery...
- agno = 0
- agno = 1
- agno = 2
- agno = 3
- process newly discovered inodes...
Phase 4 - check for duplicate blocks...
- setting up duplicate extent list...
- check for inodes claiming duplicate blocks...
- agno = 1
- agno = 3
- agno = 2
- agno = 0
No modify flag set, skipping phase 5
Phase 6 - check inode connectivity...
- traversing filesystem ...
- traversal finished ...
- moving disconnected inodes to lost+found ...
Phase 7 - verify link counts...
No modify flag set, skipping filesystem flush and exiting.
Uscita di megacli -AdpAllInfo -aAll:
Versions
================
Product Name : LSI MegaRAID SAS 9280-4i4e
Serial No : SV24919344
FW Package Build: 12.12.0-0124
Mfg. Data
================
Mfg. Date : 12/06/12
Rework Date : 00/00/00
Revision No : 04B
Battery FRU : N/A
Image Versions in Flash:
================
FW Version : 2.130.363-1846
BIOS Version : 3.25.00_4.12.05.00_0x05180000
Preboot CLI Version: 04.04-020:#%00009
WebBIOS Version : 6.0-51-e_47-Rel
NVDATA Version : 2.09.03-0039
Boot Block Version : 2.02.00.00-0000
BOOT Version : 09.250.01.219
Pending Images in Flash
================
None
PCI Info
================
Controller Id : 0000
Vendor Id : 1000
Device Id : 0079
SubVendorId : 1000
SubDeviceId : 9282
Host Interface : PCIE
ChipRevision : B4
Link Speed : 0
Number of Frontend Port: 0
Device Interface : PCIE
Number of Backend Port: 8
Port : Address
0 5003048001c1e47f
1 0000000000000000
2 0000000000000000
3 0000000000000000
4 0000000000000000
5 0000000000000000
6 0000000000000000
7 0000000000000000
HW Configuration
================
SAS Address : 500605b005a6cbc0
BBU : Present
Alarm : Present
NVRAM : Present
Serial Debugger : Present
Memory : Present
Flash : Present
Memory Size : 512MB
TPM : Absent
On board Expander: Absent
Upgrade Key : Absent
Temperature sensor for ROC : Absent
Temperature sensor for controller : Absent
Settings
================
Current Time : 14:58:51 7/11, 2016
Predictive Fail Poll Interval : 300sec
Interrupt Throttle Active Count : 16
Interrupt Throttle Completion : 50us
Rebuild Rate : 30%
PR Rate : 30%
BGI Rate : 30%
Check Consistency Rate : 30%
Reconstruction Rate : 30%
Cache Flush Interval : 4s
Max Drives to Spinup at One Time : 4
Delay Among Spinup Groups : 2s
Physical Drive Coercion Mode : Disabled
Cluster Mode : Disabled
Alarm : Enabled
Auto Rebuild : Enabled
Battery Warning : Enabled
Ecc Bucket Size : 15
Ecc Bucket Leak Rate : 1440 Minutes
Restore HotSpare on Insertion : Disabled
Expose Enclosure Devices : Enabled
Maintain PD Fail History : Enabled
Host Request Reordering : Enabled
Auto Detect BackPlane Enabled : SGPIO/i2c SEP
Load Balance Mode : Auto
Use FDE Only : No
Security Key Assigned : No
Security Key Failed : No
Security Key Not Backedup : No
Default LD PowerSave Policy : Controller Defined
Maximum number of direct attached drives to spin up in 1 min : 120
Auto Enhanced Import : No
Any Offline VD Cache Preserved : No
Allow Boot with Preserved Cache : No
Disable Online Controller Reset : No
PFK in NVRAM : No
Use disk activity for locate : No
POST delay : 90 seconds
BIOS Error Handling : Stop On Errors
Current Boot Mode :Normal
Capabilities
================
RAID Level Supported : RAID0, RAID1, RAID5, RAID6, RAID00, RAID10, RAID50, RAID60, PRL 11, PRL 11 with spanning, SRL 3 supported, PRL11-RLQ0 DDF layout with no span, PRL11-RLQ0 DDF layout with span
Supported Drives : SAS, SATA
Allowed Mixing:
Mix in Enclosure Allowed
Mix of SAS/SATA of HDD type in VD Allowed
Status
================
ECC Bucket Count : 0
Limitations
================
Max Arms Per VD : 32
Max Spans Per VD : 8
Max Arrays : 128
Max Number of VDs : 64
Max Parallel Commands : 1008
Max SGE Count : 80
Max Data Transfer Size : 8192 sectors
Max Strips PerIO : 42
Max LD per array : 16
Min Strip Size : 8 KB
Max Strip Size : 1.0 MB
Max Configurable CacheCade Size: 0 GB
Current Size of CacheCade : 0 GB
Current Size of FW Cache : 350 MB
Device Present
================
Virtual Drives : 2
Degraded : 0
Offline : 0
Physical Devices : 16
Disks : 14
Critical Disks : 0
Failed Disks : 0
Supported Adapter Operations
================
Rebuild Rate : Yes
CC Rate : Yes
BGI Rate : Yes
Reconstruct Rate : Yes
Patrol Read Rate : Yes
Alarm Control : Yes
Cluster Support : No
BBU : Yes
Spanning : Yes
Dedicated Hot Spare : Yes
Revertible Hot Spares : Yes
Foreign Config Import : Yes
Self Diagnostic : Yes
Allow Mixed Redundancy on Array : No
Global Hot Spares : Yes
Deny SCSI Passthrough : No
Deny SMP Passthrough : No
Deny STP Passthrough : No
Support Security : No
Snapshot Enabled : No
Support the OCE without adding drives : Yes
Support PFK : Yes
Support PI : No
Support Boot Time PFK Change : No
Disable Online PFK Change : No
PFK TrailTime Remaining : 0 days 0 hours
Support Shield State : No
Block SSD Write Disk Cache Change: No
Supported VD Operations
================
Read Policy : Yes
Write Policy : Yes
IO Policy : Yes
Access Policy : Yes
Disk Cache Policy : Yes
Reconstruction : Yes
Deny Locate : No
Deny CC : No
Allow Ctrl Encryption: No
Enable LDBBM : No
Support Breakmirror : No
Power Savings : No
Supported PD Operations
================
Force Online : Yes
Force Offline : Yes
Force Rebuild : Yes
Deny Force Failed : No
Deny Force Good/Bad : No
Deny Missing Replace : No
Deny Clear : No
Deny Locate : No
Support Temperature : Yes
NCQ : No
Disable Copyback : No
Enable JBOD : No
Enable Copyback on SMART : No
Enable Copyback to SSD on SMART Error : Yes
Enable SSD Patrol Read : No
PR Correct Unconfigured Areas : Yes
Enable Spin Down of UnConfigured Drives : Yes
Disable Spin Down of hot spares : No
Spin Down time : 30
T10 Power State : No
Error Counters
================
Memory Correctable Errors : 0
Memory Uncorrectable Errors : 0
Cluster Information
================
Cluster Permitted : No
Cluster Active : No
Default Settings
================
Phy Polarity : 0
Phy PolaritySplit : 0
Background Rate : 30
Strip Size : 256kB
Flush Time : 4 seconds
Write Policy : WB
Read Policy : Adaptive
Cache When BBU Bad : Disabled
Cached IO : No
SMART Mode : Mode 6
Alarm Disable : Yes
Coercion Mode : None
ZCR Config : Unknown
Dirty LED Shows Drive Activity : No
BIOS Continue on Error : 0
Spin Down Mode : None
Allowed Device Type : SAS/SATA Mix
Allow Mix in Enclosure : Yes
Allow HDD SAS/SATA Mix in VD : Yes
Allow SSD SAS/SATA Mix in VD : No
Allow HDD/SSD Mix in VD : No
Allow SATA in Cluster : No
Max Chained Enclosures : 16
Disable Ctrl-R : Yes
Enable Web BIOS : Yes
Direct PD Mapping : No
BIOS Enumerate VDs : Yes
Restore Hot Spare on Insertion : No
Expose Enclosure Devices : Yes
Maintain PD Fail History : Yes
Disable Puncturing : No
Zero Based Enclosure Enumeration : No
PreBoot CLI Enabled : Yes
LED Show Drive Activity : Yes
Cluster Disable : Yes
SAS Disable : No
Auto Detect BackPlane Enable : SGPIO/i2c SEP
Use FDE Only : No
Enable Led Header : No
Delay during POST : 0
EnableCrashDump : No
Disable Online Controller Reset : No
EnableLDBBM : No
Un-Certified Hard Disk Drives : Allow
Treat Single span R1E as R10 : No
Max LD per array : 16
Power Saving option : Don't Auto spin down Configured Drives
Max power savings option is not allowed for LDs. Only T10 power conditions are to be used.
Default spin down time in minutes: 30
Enable JBOD : No
TTY Log In Flash : No
Auto Enhanced Import : No
BreakMirror RAID Support : No
Disable Join Mirror : No
Enable Shield State : No
Time taken to detect CME : 60s
Uscita di megacli -AdpBbuCmd -GetBbuSTatus -aAll:
BBU status for Adapter: 0
BatteryType: iBBU
Voltage: 4068 mV
Current: 0 mA
Temperature: 30 C
Battery State: Optimal
BBU Firmware Status:
Charging Status : Charging
Voltage : OK
Temperature : OK
Learn Cycle Requested : No
Learn Cycle Active : No
Learn Cycle Status : OK
Learn Cycle Timeout : No
I2c Errors Detected : No
Battery Pack Missing : No
Battery Replacement required : No
Remaining Capacity Low : No
Periodic Learn Required : No
Transparent Learn : No
No space to cache offload : No
Pack is about to fail & should be replaced : No
Cache Offload premium feature required : No
Module microcode update required : No
GasGuageStatus:
Fully Discharged : No
Fully Charged : No
Discharging : Yes
Initialized : Yes
Remaining Time Alarm : No
Discharge Terminated : No
Over Temperature : No
Charging Terminated : No
Over Charged : No
Relative State of Charge: 88 %
Charger System State: 49169
Charger System Ctrl: 0
Charging current: 512 mA
Absolute state of charge: 87 %
Max Error: 4 %
Exit Code: 0x00
Uscita di megacli -LDInfo -Lall -aAll:
Adapter 0 -- Virtual Drive Information:
Virtual Drive: 0 (Target Id: 0)
Name :
RAID Level : Primary-1, Secondary-0, RAID Level Qualifier-0
Size : 111.281 GB
Sector Size : 512
Mirror Data : 111.281 GB
State : Optimal
Strip Size : 256 KB
Number Of Drives : 2
Span Depth : 1
Default Cache Policy: WriteBack, ReadAhead, Direct, No Write Cache if Bad BBU
Current Cache Policy: WriteBack, ReadAhead, Direct, No Write Cache if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy : Disk's Default
Encryption Type : None
Is VD Cached: No
Virtual Drive: 1 (Target Id: 1)
Name :
RAID Level : Primary-1, Secondary-0, RAID Level Qualifier-0
Size : 1.633 TB
Sector Size : 512
Mirror Data : 1.633 TB
State : Optimal
Strip Size : 256 KB
Number Of Drives per span:2
Span Depth : 6
Default Cache Policy: WriteBack, ReadAhead, Direct, Write Cache OK if Bad BBU
Current Cache Policy: WriteBack, ReadAhead, Direct, Write Cache OK if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy : Disk's Default
Encryption Type : None
Is VD Cached: No
Aggiornamento: su consiglio di Andrew, ho eseguito ddalcuni minuti per vedere che tipo di throughput avrei ottenuto sulle letture del disco grezzo:
dd if=/dev/sdb of=/dev/null bs=256k
19701+0 records in
19700+0 records out
5164236800 bytes (5.2 GB) copied, 202.553 s, 25.5 MB/s
Risultati di altre esecuzioni, con throughput altamente variabile:
18706857984 bytes (19 GB) copied, 1181.51 s, 15.8 MB/s
20923023360 bytes (21 GB) copied, 388.137 s, 53.9 MB/s
21205876736 bytes (21 GB) copied, 55.5997 s, 381 MB/s
25391005696 bytes (25 GB) copied, 153.903 s, 165 MB/s
Aggiornamento 2: output di megacli -PDlist -aall: https://gist.github.com/danpelota/3fca1e5f90a1f358c2d52a49bfb08ef0
@Dan, ho guardato in dettaglio l'
—
Michal Sokolowski
megacli -PDlist -aalloutput e non vedo nulla ovviamente sbagliato lì, smartctl -a -d sat+megaraid,10 /dev/sdbera solo un esempio, controllare i contatori SMART vale lo scatto IMHO, gli avvisi SMART raramente hanno funzionato per me, per prima cosa trovare le impostazioni del modulo corrette per le unità utilizzando smartctl --scan, quindi sostituire parte sat+megaraid,21congedo /dev/sdaintatta, non dovrebbe cambiare nulla comunque. Ho usato in questo modo ServeRAID M5015 SAS/SATA Controller, sembra però la stessa merda. Ecco un esempio: pastebin.com/WYb8Utxr
@Dan, per me tale comportamento è ancora costituito da dischi "prefailing". È possibile che alcuni dischi recuperino quasi sempre le letture, rallentando l'intero processo. Le statistiche SMART sono fondamentali per approvare / rifiutare la mia teoria. Ancora una volta, per me i contatori megaraid erano inutili, non è cambiato fino a quando il disco non è morto completamente (lo stato in cui non si avvia affatto), ho usato SAS simili in termini di fornitore e dimensioni.
—
Michal Sokolowski il
@MichalSokolowski: ha senso. Ha ottenuto i numeri di dispositivo corretti ed eseguito
—
danpelota
smartctlsui singoli dischi. Sembra che il conteggio degli errori non medi sia enorme per il disco 18: gist.github.com/danpelota/83b54854aa5af2e351ed71af5c8ebbf5
Sono contento che tu l'abbia inchiodato. Non esitate a farlo. Lo voterò comunque. L'aumento della reputazione è solo un effetto collaterale. Ricorda di rispondere alla domanda. Hai fatto la maggior parte del lavoro. :) Ho letto le tue statistiche SMART, ma nella forma attuale sono anche inutili. Volevo vedere i contatori SMART reali. Stranamente il tuo
—
Michal Sokolowski il
smartctlnon lo mostra come il mio. C'è una risposta effettiva di sicuro.
dd if=/dev/sdb of=/dev/null bs=256ke vedere quale larghezza di banda si ottiene. Assicurati solo di non scrivere sul dispositivo disco a meno che tu non voglia ripristinare i tuoi filesystem dal backup ...