Пример настройки параметров ядра Linux для работы DB2

Использован образ 2016-12-16-17-img

http://www.ibm.com/support/knowledgecenter/en/SSEPGG_9.7.0/com.ibm.db2.luw.qb.server.doc/doc/t0008238.html

На компьютере с 24Gb RAM

# ipcs -l

------ Пределы совм. исп. памяти --------
максимальное количество сегментов = 4096      // SHMMNI

максимальный размер сегмента (кбайт) = 32768  // SHMMAX

max total shared memory (kbytes) = 8388608    // SHMALL

минимальный размер сегмента (байт) = 1

------ Пределы семафоров --------
максимальное количество массивов = 128        // SEMMNI

максимум семафоров на массив = 250            // SEMMSL
максимум семафоров на всю систему = 32000     // SEMMNS

максимум операций на вызов семафора = 32      // SEMOPM

максимальное значение семафора = 32767

------ Лимиты сообщений --------
максимум очередей для всей системы = 32768    // MSGMNI

максимальный размер сообщения (байт) = 8192   // MSGMAX

максимальный по умолчанию размер

сообщения (байт) = 16384                      // MSGMNB 

http://www.ibm.com/support/knowledgecenter/en/SSEPGG_9.7.0/com.ibm.db2.luw.qb.server.doc/doc/c0057140.html 

IPC kernel parameter

	Enforced minimum setting for Version 9.7 Fix Pack 1 or earlier	Enforced minimum setting for Version 9.7 Fix Pack 2 or later fix packs
kernel.shmmni (SHMMNI)	no value is enforced	256 * <size of RAM in GB>
kernel.shmmax (SHMMAX)	268 435 456 (32-bit kernel) 1 073 741 824 (64-bit kernel)	<size of RAM in bytes>1
kernel.shmall (SHMALL)	no value is enforced	2 * <size of RAM in the default system page size>2
kernel.sem (SEMMNI)	1 024	256 * <size of RAM in GB>
kernel.sem (SEMMSL)	no value is enforced	250
kernel.sem (SEMMNS)	no value is enforced	256 000
kernel.sem (SEMOPM)	no value is enforced	32
kernel.msgmni (MSGMNI)	1 024	1 024 * <size of RAM in GB>
kernel.msgmax (MSGMAX)	65 536	65 536
kernel.msgmnb (MSGMNB)	65 536	65 536 3
On 32-bit Linux operating systems, the enforced minimum setting for SHMMAX is limited to 4 294 967 295 bytes. SHMALL limits the total amount of virtual shared memory that can be allocated on a system. Each DB2 data server efficiently manages the amount of system memory it consumes, also know as committed memory. The DB2 data server allocates more virtual memory than it commits to support memory preallocation and dynamic memory management. Memory preallocation benefits performance. Dynamic memory management is the process of growing and shrinking real memory usage within separate virtual shared memory areas. To support memory preallocation and dynamic memory management, effectively, it is frequently necessary for data servers to allocate more virtual shared memory on a system than the amount of physical RAM. The kernel requires this value as a number of pages. Load performance might benefit from a larger message queue size limit, specified in bytes by MSGMNB. You can view message queue usage can by running the ipcs -q command. If the message queues are at capacity, or reaching capacity, during load operations, consider increasing the number of bytes the message queue size limit. Before DB2 Version 9.7 Fix Pack 3, if a message queue became full, the DB2 Version 9.7 load utility failed with SQL2044N. For more information about MSGMNB settings, see APAR IC65152.

Если RAM 8Gb 

kernel.shmmax=8589934592kernel.shmall=8589934592/4096*2=4194304

kernel.shmmni=256*8=2048 

Если RAM 16Gb

kernel.shmmax=17179869184 

kernel.shmall=17179869184/4096*2=8388608

kernel.shmmni=256*16=4096

Если RAM 24Gb 

kernel.shmmax=25769803776

kernel.shmall=25769803776/4096*2=12582912

kernel.shmmni=256*24=6144

---------------------------------------------------- 

# nano /etc/sysctl.conf

#Example for a computer with 24GB of RAM:
kernel.shmmni=6144
kernel.shmmax=25769803776
kernel.shmall=12582912
#kernel.sem=<SEMMSL> <SEMMNS> <SEMOPM> <SEMMNI>
kernel.sem=250 256000 32 6144
kernel.msgmni=24576
kernel.msgmax=65536
kernel.msgmnb=65536

Run sysctl with -p parameter
to load in sysctl settings from the default file /etc/sysctl.conf: 

# sysctl -p

kernel.shmmni = 6144
kernel.shmmax = 25769803776
kernel.shmall = 12582912
kernel.sem = 250 256000 32 6144
kernel.msgmni = 24576
kernel.msgmax = 65536
kernel.msgmnb = 65536
 

---------------------------------------------------- 

Подготовим систему для установки db2 ./setup

# apt-get install libaio1 ksh libstdc++6-4.4-dev libstdc++6-4.4-pic

# apt-get install libpam0g:i386

# ln -s /lib/i386-linux-gnu/libpam.so.0 /lib/libpam.so

as root 

# echo 0 > /proc/sys/kernel/randomize_va_space
 

as sudo user  $ sudo sh -c "echo 0 > /proc/sys/kernel/randomize_va_space"  

Подготовленный для установки образ сохраним.

Сохранение SSD

2016-12-17-15-img