Mysql (Percona-server5.5)在导入过程中完全停止(myloader)

Question

在配置我们的新服务器(IBM X3650M4、2 xIntelXeonE5-2620、64 RAID、RAID 10 (4x240gSSD))时，我们遇到了一个奇怪的问题。我们正在尝试将转储(mydumper)从我们(旧的)生产环境导入到我们的新环境中，但是我们很难做到这一点。

转储为47G (压缩)、+/- 4500个表，最大的表为7.1G (54285914行)、2.2G、1.7G和1.7G。

我们试图使用12个(或8个)线程运行myloader，但大多数情况下都失败了。几分钟后，myloader来到了大桌子和摊位。有几个工具不再显示活动(htop没有cpu负载，iostat没有写或读)，mytop显示了4(长时间运行的)从未完成的查询，大多数innotop屏幕被冻结(因为SHOW INNODB STATUS不再返回任何结果)。当我试图重新启动mysql时，这也会失败，因为mysql无法杀死许多线程。唯一的解决办法是使用killall -9 mysqld mysql。

我们使用以下mysql配置：

# cat /etc/mysql/my.cnf 
# Ansible managed

[client]
port = 3306
socket = /var/run/mysqld/mysqld.sock

ssl_cert = /etc/mysql/client-cert.pem
ssl_key = /etc/mysql/client-key.pem

[mysqld_safe]
socket = /var/run/mysqld/mysqld.sock
nice = 0

[mysqld]
user = mysql
socket = /var/run/mysqld/mysqld.sock
pid_file = /var/run/mysqld/mysqld.pid
port = 3306
basedir = /usr
datadir = /var/lib/mysql
tmpdir = /tmp
lc_messages_dir = /usr/share/mysql

general_log = 0
general_log_file = /var/log/mysql/mysql.log
log_error = /var/log/mysql/error.log
log_queries_not_using_indexes = 0
slow_query_log = 0
slow_query_log_file = /var/log/mysql/mysql-slow.log

skip_external_locking = 1
skip_name_resolve = 1

max_connections = 1000
wait_timeout = 28800
interactive_timeout = 28800

sql_mode = NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

character_set_server = utf8
collation_server = utf8_general_ci
skip-character-set-client-handshake
init_connect='SET collation_connection = utf8_general_ci; SET NAMES utf8;'

default_storage_engine = InnoDB

key_buffer_size = 32M
myisam_recover_options = FORCE,BACKUP

thread_stack = 256K
thread_cache_size = 500

query_cache_type = 0
query_cache_limit = 2M
query_cache_size = 64M

max_allowed_packet = 256M
group_concat_max_len = 256M

tmp_table_size = 256M
max_heap_table_size = 64M

open_files_limit = 65535
innodb_open_files = 8192
table_definition_cache = 8192
table_open_cache = 8192

expire_logs_days = 7
max_binlog_size = 1G

innodb_buffer_pool_size = 32G
innodb_additional_mem_pool_size = 64M
innodb_log_file_size = 512M
innodb_log_buffer_size = 16M
innodb_flush_log_at_trx_commit = 2
innodb_flush_method = O_DIRECT
innodb_thread_concurrency = 0
innodb_write_io_threads = 8
innodb_read_io_threads = 8
innodb_io_capacity = 25000

innodb_file_per_table
innodb_stats_on_metadata = 0

innodb_adaptive_flushing_method = keep_average
innodb_flush_neighbor_pages = none
log_warnings_suppress = 1592
query_response_time_stats = 1

ssl_ca = /etc/mysql/ca-cert.pem
ssl_cert = /etc/mysql/server-cert.pem
ssl_key = /etc/mysql/server-key.pem

[mysqldump]
quick
quote-names
max_allowed_packet = 256M

[mysql]

[isamchk]
key_buffer_size = 32M

!includedir /etc/mysql/conf.d/

我们使用以下ext4挂载选项：

defaults,noatime,nobarrier

我们使用以下raid (控制器)设置：

# ./MegaCli64 -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                : 445.171 GB
Sector Size         : 512
Is VD emulated      : No
Mirror Data         : 445.171 GB
State               : Optimal
Strip Size          : 128 KB
Number Of Drives per span:2
Span Depth          : 2
Default Cache Policy: WriteThrough, ReadAhead, Direct, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Direct, No Write Cache if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy   : Disabled
Encryption Type     : None
PI type: No PI

Is VD Cached: No


Virtual Drive: 1 (Target Id: 1)
Name                :
RAID Level          : Primary-1, Secondary-0, RAID Level Qualifier-0
Size                : 930.390 GB
Sector Size         : 512
Is VD emulated      : No
Mirror Data         : 930.390 GB
State               : Optimal
Strip Size          : 128 KB
Number Of Drives    : 2
Span Depth          : 1
Default Cache Policy: WriteThrough, ReadAhead, Direct, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Direct, No Write Cache if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy   : Disabled
Encryption Type     : None
PI type: No PI

Is VD Cached: No



Exit Code: 0x00

和

# ./MegaCli64 -AdpAllInfo -a0

Adapter #0

==============================================================================
                    Versions
                ================
Product Name    : ServeRAID M5110e
Serial No       : 31R0NE          
FW Package Build: 23.22.0-0024

                    Mfg. Data
                ================
Mfg. Date       : 01/24/13
Rework Date     : 01/24/13
Revision No     :  00W2671
Battery FRU     :         

                Image Versions in Flash:
                ================
BIOS Version       : 5.45.07.2_4.16.08.00_0x06030503
FW Version         : 3.340.75-3372
NVDATA Version     : 2.1312.03-0126
WebBIOS Version    : 6.1-71-e_71-Rel
Preboot CLI Version: 05.07-00:#%00011
Boot Block Version : 2.05.00.00-0010
BOOT Version       : 07.26.26.219

                Pending Images in Flash
                ================
None

                PCI Info
                ================
Controller Id   : 0000
Vendor Id       : 1000
Device Id       : 005b
SubVendorId     : 1014
SubDeviceId     : 0412

Host Interface  : PCIE

ChipRevision    : D1

Link Speed       : 0 
Number of Frontend Port: 0 
Device Interface  : PCIE

Number of Backend Port: 8 
Port  :  Address
0        4433221100000000 
1        4433221101000000 
2        4433221102000000 
3        4433221103000000 
4        4433221104000000 
5        4433221105000000 
6        0000000000000000 
7        0000000000000000 

                HW Configuration
                ================
SAS Address      : 500507605803cfa8
BBU              : Present
Alarm            : Present
NVRAM            : Present
Serial Debugger  : Present
Memory           : Present
Flash            : Present
Memory Size      : 512MB
TPM              : Absent
On board Expander: Absent
Upgrade Key      : Present
Temperature sensor for ROC    : Present
Temperature sensor for controller    : Absent

ROC temperature : 59  degree Celsius

                Settings
                ================
Current Time                     : 20:52:13 11/12, 2015
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 : 2
Delay Among Spinup Groups        : 12s
Physical Drive Coercion Mode     : 1GB
Cluster Mode                     : Disabled
Alarm                            : Disabled
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                     : Yes
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 : 10 
Auto Enhanced Import             : No
Any Offline VD Cache Preserved   : No
Allow Boot with Preserved Cache  : No
Disable Online Controller Reset  : No
PFK in NVRAM                     : Yes
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

                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            : 60 
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       : 368 MB

                Device Present
                ================
Virtual Drives    : 2 
  Degraded        : 0 
  Offline         : 0 
Physical Devices  : 7 
  Disks           : 6 
  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                 : Yes
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                : Yes
Snapshot Enabled                : No
Support the OCE without adding drives : Yes
Support PFK                     : Yes
Support PI                      : Yes
Support Boot Time PFK Change    : Yes
Disable Online PFK Change       : Yes
Support LDPI Type1                      : No
Support LDPI Type2                      : No
Support LDPI Type3                      : No
PFK TrailTime Remaining         : 0 days 0 hours
Support Shield State            : Yes
Block SSD Write Disk Cache Change: No
Support Online FW Update    : Yes

                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                                     : Yes
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
                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                       : 128kB
Flush Time                       : 4 seconds
Write Policy                     : WB
Read Policy                      : Adaptive
Cache When BBU Bad               : Disabled
Cached IO                        : No
SMART Mode                       : Mode 6
Alarm Disable                    : No
Coercion Mode                    : 1GB
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     : No
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               : Yes
Zero Based Enclosure Enumeration : No
PreBoot CLI Enabled              : Yes
LED Show Drive Activity          : Yes
Cluster Disable                  : No
SAS Disable                      : No
Auto Detect BackPlane Enable     : SGPIO/i2c SEP
Use FDE Only                     : Yes
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              : All power saving options are disabled
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              : Yes
Time taken to detect CME         : 60s

Exit Code: 0x00

和

# ./MegaCli64 -PDList -a0

Adapter #0

Enclosure Device ID: 252
Slot Number: 0
Drive's position: DiskGroup: 0, Span: 0, Arm: 0
Enclosure position: N/A
Device Id: 0
WWN: 50025385700191ba
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 223.570 GB [0x1bf244b0 Sectors]
Non Coerced Size: 223.070 GB [0x1be244b0 Sectors]
Coerced Size: 222.585 GB [0x1bd2c000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: 203Q
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221100000000
Connected Port Number: 0(path0) 
Inquiry Data: S1G0NWAG600282      SAMSUNG MZ7WD240HCFV-00003              DXM9203Q
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Solid State Device
Drive:  Not Certified
Drive Temperature :34C (93.20 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No



Enclosure Device ID: 252
Slot Number: 1
Drive's position: DiskGroup: 0, Span: 0, Arm: 1
Enclosure position: N/A
Device Id: 1
WWN: 50025385700191c6
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 223.570 GB [0x1bf244b0 Sectors]
Non Coerced Size: 223.070 GB [0x1be244b0 Sectors]
Coerced Size: 222.585 GB [0x1bd2c000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: 203Q
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221101000000
Connected Port Number: 1(path0) 
Inquiry Data: S1G0NWAG600294      SAMSUNG MZ7WD240HCFV-00003              DXM9203Q
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Solid State Device
Drive:  Not Certified
Drive Temperature :33C (91.40 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No



Enclosure Device ID: 252
Slot Number: 2
Drive's position: DiskGroup: 0, Span: 1, Arm: 0
Enclosure position: N/A
Device Id: 2
WWN: 50025385700191c2
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 223.570 GB [0x1bf244b0 Sectors]
Non Coerced Size: 223.070 GB [0x1be244b0 Sectors]
Coerced Size: 222.585 GB [0x1bd2c000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: 203Q
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221102000000
Connected Port Number: 2(path0) 
Inquiry Data: S1G0NWAG600290      SAMSUNG MZ7WD240HCFV-00003              DXM9203Q
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Solid State Device
Drive:  Not Certified
Drive Temperature :33C (91.40 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No



Enclosure Device ID: 252
Slot Number: 3
Drive's position: DiskGroup: 0, Span: 1, Arm: 1
Enclosure position: N/A
Device Id: 3
WWN: 50025385700191b7
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 223.570 GB [0x1bf244b0 Sectors]
Non Coerced Size: 223.070 GB [0x1be244b0 Sectors]
Coerced Size: 222.585 GB [0x1bd2c000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: 203Q
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221103000000
Connected Port Number: 3(path0) 
Inquiry Data: S1G0NWAG600279      SAMSUNG MZ7WD240HCFV-00003              DXM9203Q
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Solid State Device
Drive:  Not Certified
Drive Temperature :35C (95.00 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No



Enclosure Device ID: 252
Slot Number: 4
Drive's position: DiskGroup: 1, Span: 0, Arm: 0
Enclosure position: N/A
Device Id: 4
WWN: 5000c5004f547de9
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 931.512 GB [0x74706db0 Sectors]
Non Coerced Size: 931.012 GB [0x74606db0 Sectors]
Coerced Size: 930.390 GB [0x744c8000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: HPGD
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221104000000
Connected Port Number: 4(path0) 
Inquiry Data: Z1N3AYLE            MB1000GCEHH                             HPGD    
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Hard Disk Device
Drive:  Not Certified
Drive Temperature :34C (93.20 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No



Enclosure Device ID: 252
Slot Number: 5
Drive's position: DiskGroup: 1, Span: 0, Arm: 1
Enclosure position: N/A
Device Id: 5
WWN: 5000c5004f547bb5
Sequence Number: 2
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 931.512 GB [0x74706db0 Sectors]
Non Coerced Size: 931.012 GB [0x74606db0 Sectors]
Coerced Size: 930.390 GB [0x744c8000 Sectors]
Sector Size:  512
Logical Sector Size:  512
Physical Sector Size:  512
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: HPGD
Shield Counter: 0
Successful diagnostics completion on :  N/A
SAS Address(0): 0x4433221105000000
Connected Port Number: 5(path0) 
Inquiry Data: Z1N3AZR2            MB1000GCEHH                             HPGD    
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None 
Device Speed: 6.0Gb/s 
Link Speed: 6.0Gb/s 
Media Type: Hard Disk Device
Drive:  Not Certified
Drive Temperature :34C (93.20 F)
PI Eligibility:  No 
Drive is formatted for PI information:  No
PI: No PI
Drive's NCQ setting : Enabled
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s 
Drive has flagged a S.M.A.R.T alert : No




Exit Code: 0x00

编辑1:我们使用的是：

• Percona服务器5.5.46-37.5
• mydumper 0.6.2 (建于MySQL 5.5.45-37.4)
• 内核3.13.0-68-通用#111-Ubuntu星期五11月6日18:17:06 UTC 2015 x86_64 GNU/Linux

编辑2:问题与以下方面无关：

• myloader，mysql客户端在使用多个进程导入时有相同的问题。
• 服务器的RAM (测试)
• RAID控制器的RAM (测试)
• 当mysqld绑定到一个CPU时，导入也会暂停。

编辑3：

• MariaDB (mysqld Ver 5.5.46-MariaDB-1ubuntu0.14.04.2 for debian-linux-gnu on x86_64 ((Ubuntu)))似乎没有这个问题。

编辑4：

问题似乎是由以下四种设置之一造成的：

• innodb_adaptive_flushing_method = keep_average
• innodb_flush_neighbor_pages = none
• log_warnings_suppress = 1592
• query_response_time_stats = 1

编辑5：

这个问题似乎是由以下原因引起的：innodb_adaptive_flushing_method = keep_average，innodb_adaptive_flushing_method = estimate运行稳定

编辑6：

问题似乎是由：innodb_adaptive_flushing_method = keep_average引起的，但只有在Percona上，MariaDB似乎运行稳定(设置相同)

奇怪的是，我们能够在其他(较慢的)机器上很好地导入转储，主要区别是它们有一个较小的缓冲池(<= 12G)，功能较弱的CPU (Intel(R) Xeon(R) CPU E3-1246 v3 @ 3.50GHz或Intel(R) Core(TM) i7-3930K CPU @ 3.20GHz)，只有一个SSD (或带有2的软件raid 1)。

我们真的很好奇这个问题的原因是什么。

Answer 1

当某些检查点/刷新配置导致失速时，存在一个已知的问题。以下是Percona5.5文档改进的InnoDB I/O可伸缩性的引文：

通常，检查点是在当前最古老的页面修改(这称为“模糊检查点”)时被动完成的。当检查点年龄接近最大检查点年龄(由所有事务日志文件的总长度确定)时，InnoDB试图通过刷新许多脏块来保持检查点的最大年龄。但是，如果每秒有许多更新，而且许多块几乎具有相同的修改时间，那么大量的刷新可能会导致中断。... keep_average 2：该方法尝试使用比其他方法(1.0秒)更短的循环周期(0.1秒)来保持I/O速率不变。它是为SSD卡而设计的。

keep_average被设计为与比SSD磁盘更快的SSD卡一起使用。在您的示例中，InnoDB使用非常短的周期来刷新脏页。然后，按照文档的说法，太多的带有非常紧的时间戳的页面会导致拥塞和停滞。除非您使用的SSD卡，如融合IO，您不应该使用此设置。

希望这能有所帮助。

Answer 2

这不是一种不正常的行为，我经常在类似的硬件(更多内存，但更糟的磁盘)下使用mydumper，而且它根本没有这种行为(即使我的数据集大30倍)。关于您的特定配置，我有很多不喜欢的地方(我将至少使用5.6进行新安装，我将删除QCache，将RAID设置为写回-not WT，您的小条大小，禁用导入进程的二进制日志，如果它是专用硬件，则增加缓冲池和事务日志，在使用异步io时读取io线程，.)但是，所有这些都只会提高性能，而不会使它变得如此糟糕，以至于无法忍受。

遗憾的是，没有控制台在我面前没有什么可说的，只是您应该监视导入时正在发生的事情(监视插入速率、处理程序、innodb统计数据、潜在的OS硬件/暂存)。也许检查一下RAID是否处于电池学习模式。肯定出了什么问题: DB争用，磁盘问题？尝试执行磁盘速度基准测试。使用详细的输出执行myloader。尝试使用常规命令: lsof、iotop、htop、vmstat、dmesg。如果一切都失败了，请使用perf来分析mysqld二进制文件，看看您在浪费周期。也许您是因为FlushLatTxC=2而过度占用文件系统内存？也许你们是在交换而你没有意识到这一点？检查您的mydumper和PS版本。您是否会遇到旧内核中存在的异步IO问题？

对不起，在这里我无能为力。

Answer 3

确保您已经拥有: set foreign_key_checks=0；set sql_log_bin=0；set unique_checks=0；我现在要取消激活二进制日志。关闭慢速查询日志。如果可以，则在加载后创建索引(加载数据所需的时间将取决于您有多少索引、索引的类型以及数据类型。文本字段(blob)需要很长时间才能加载。降低线程数。