qyt_2010-优快云博客

原创 Some lazy tips for Mysql about calculation

1.select * from information_schema.innodb_trx where TIME_TO_SEC(timediff(now(),trx_started))>60;-> can calculate the trx which exceed the indicated time(60s is from the example)(To Be Continued)

2022-01-13 09:39:57 303

原创 The difference between actual installed memory and the output from free command

Symptom:Why less memory is seen from the 'free' command output compared to what has been actually allocated to the server?Solution:Pls see the dmesg as bellowMemory: 131417224K/134082252K available (7571K kernel code, 1587K rwdata, 3900K rodata, 202

2021-12-08 10:47:27 164

原创 Why the size of select is not so large but stuck at ‘sending data‘ status?

Symptom:Mysql Client want to fetch about 200 lines data from mysql server.From the mysql server end, it stuck at 'sending data' status for a long time.Solution:1. First, pls check the Netwerk IO and HW network status.-> low possibility2. Che

2021-11-24 11:00:16 526

原创 Mysql---terminate called after throwing an instance of ‘std::bad_alloc

Sysptom:InnoDB: page_cleaner: 1000ms intended loop took 7119ms. The settings might not be optimal. (flushed=208 and evicted=0, during the time.)InnoDB: page_cleaner: 1000ms intended loop took 10336ms. The settings might not be optimal. (flushed=208 and

2021-11-18 15:28:35 1101

原创 [ERROR] Failed to open log (file ‘/mysqllogs/logs/*****‘, errno 2)

Production:Mysql ServerSysptom:2021-11-18T02:41:00.473687Z 0 [Note] InnoDB: Buffer pool(s) load completed at 211118 10:41:00mysqld: File '/mysqllogs/logs/****' not found (Errcode: 2 - No such file or directory)2021-11-18T02:41:00.473953Z 0 [ERROR

2021-11-18 14:29:10 623

原创 Recover Corrupted Root Partition from Rescue Mode

Issue:Recover the root partition, this is a critical issue.Solution:Checking all file systems.[/sbin/fsck.ext3 (1) -- /] fsck.ext3 -a /dev/VolGroup00/LogVol00/dev/VolGroup00/LogVol00 contains a file system with errors, check forced./dev/VolGroup

2021-11-18 09:06:30 85

原创 kernel: [ 3166.869181] EDAC MC2: 1 CE memory read error on CPU_SrcID#1_Ha#1_Chan#1_DIMM#0

Sysptom:Sun Nov 14 19:08:17 2021 ID ffff P1 ECC CE /SYS/MB/P1/D3, 1 errors on MC1-CH1, dimm 0, rank 0.Sun Nov 14 19:08:17 2021 ID ffff ******** Home Agent(HA1) Shadow Errors ********Sun Nov 14 19:15:08 2021 ID ffff P1 ECC CE /SYS/MB/P1/D3, 1 errors on.

2021-11-15 09:41:08 2138

原创 Server Crash with Error “sysrq: SysRq : Trigger a crash“

Linux Server crashed, We always need vmcore to do the further investigation.The vmcore file shows below；WARNING: kernel relocated [928MB]: patching 89859 gdb minimal_symbol valuesKERNEL: /share/linuxrpm/vmlinux_repo/64/4.14.35-1818.3.3.el7uek.x86

2021-10-20 11:03:23 1038

原创 How to calculate the whole physical memory has been used by progress.

Goal:How to calculate the whole physical memory has been used by progress? In the other word, how to calculate the sum of whole progress used physical memory ?I got this SR or ticket from one customer and I would like to do it with the method bellow.

2021-10-19 18:19:41 92

原创 Is There a Way to Prevent MySQL From Crashing When There is No Memory Available

Sometimes Mysql service will be killed by OOM Killer for lack of memory.But unfortunately, there is no way to prevent the OOM killing the mysql.There is no way is to monitor the mysql time by time, and set alter to it.If it exceed the threshold, you

2021-10-15 12:24:42 108

原创 Some user use Tape driver to backup and server always crash

When the user is using tape device, always meet io high situation.So if you enable hung_task_panic, mean hung_task_panic=1, when the device time out, the server will be reboot for the time_outLike:[1817156.683888] INFO: task tldd:53185 blocked for mo

2021-10-12 16:31:34 186

原创 Restart&Recovery Mysql after hit ‘missing MLOG_CHECKPOINT‘ error

1. shutdown the mysql service, make sure the service is not running2. backup the files in the data directory, you may just rename it and then create a new data directory3. You can find the data directory using the command below:select @@datadir;Or you

2021-10-12 13:03:08 97

原创 Server reboot by Oracle RMAN backup

우선 HW 상 확인되는대로 모두 정상입니다.==-bash-4.2$ less megacli64-FwTermLog.out | grep -i 'fatal'39_2 2021-08-30T03:44:27+09:00 clear "Check for configuration of DiskController is successful." >>> 관련된 disk controller fatal error 발견되지 않습니다...

2021-10-09 12:09:54 1167

原创 HBA card got the OCR - Online Controller reset

-- Server details;FRU Device Description : TOP_LEVEL_PROD (LUN 0, ID 250)Product Manufacturer : Oracle CorporationProduct Name : Exadata X8-2Product Part Number : Exadata X8-2Product Serial : AK00635988FRU Device Description : /SYS...

2021-10-01 10:12:14 762

原创 Exadata Storage Cell 로 부터 ONLINE 디스크를 교체할 때 ASM 에서 확인하여야 할 항목들

적용 대상:Oracle Exadata Storage Server Software - 버전 11.1.0.3.0 과(와) 그 후속Exadata Database Machine X2-2 Hardware - 버전 All Versions to All Versions [릴리즈 All Releases]Oracle Solaris on x86-64 (64-bit)Linux x86-64목적다양한 이유로 인하여 (예를 들어 미디어 오류 카운트 증가) 엑사데이터

2021-09-30 08:58:13 523

原创 Mysql slave not synching with master

Got this case from "Duke University Health System, Inc"Sysmptom/IssueLast_Error: Could not execute Update_rows event on table redcap.redcap_data; Can't find record in 'redcap_data', Error_code: 1032; Can't find record in 'redcap_data', Error_code:

2021-09-27 15:33:06 119

原创 Sun/Oracle X86システム上でILOMスナップショットを採取する方法

適用範囲:Sun Netra X4250 Server - バージョン Not Applicable 以降Sun Netra X4270 Server - バージョン Not Applicable 以降Sun Server X2-8 - バージョン Not Applicable 以降Sun Fire X2250 Server - バージョン Not Applicable 以降Sun Fire X4600 Server - バージョン Not Applicable 以降この文書の内容はすべてのプ

2021-09-26 17:48:23 242

原创 server auto reboot for memory ce error

Server_Model=ORACLE_SERVER_X6-2====START SERIAL NUMBERS======Motherboard, from dmidecode==--System serial--1719NM190B5 2021-09-21T19:57:55+09:00 warning "A kernel crash has caused the system to reboot."-bash-4.2$ less physicaldisk...

2021-09-23 10:47:11 789

原创 Oracle Linux: How to Provide “sudo“ Access to non-root User for all Commands

Applies to:Linux OS - Version Oracle Linux 5.0 and laterLinux x86GoalThis document explains how to provide sudo access for non-root user for all commandsSolutionRun "visudo" and uncomment the following line (if commented): # %wheel ALL=(...

2021-08-25 14:13:08 80

原创日本語 SRDC - Oracle Database Appliance(ODA) sundiagの収集

適用範囲Oracle Database Appliance 全てのバージョン何が収集され、何故収集するか。このドキュメントはサービス・リクエスト・データ収集 (SRDC) としてタグ付けされています。これは、読者に必要な手順を提供するために特別に設計されていることを意味します。Oracle Database Appliance(ODA) sundiagの収集root ユーザにて1つのODAノード上で実行する:# /root/Extras/odasundiag.sh実行すると、日付

2021-08-25 13:58:12 265

原创 Mysql-Change Definer In Stored Procedure

Created from SR 3-7760169791 Applies to: MySQL Server - Version 5.0 and later Goal Change the definer of a stored procedure Solution It is possible to change the definer of a procedure by editing the mysql.proc table dir.

2021-08-24 16:19:25 137