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---
features:
  - |
    Enable innodb_flush_log_at_trx_commit configuration for Galera only.
upgrade:
  - |
    Setting the innodb_flush_log_at_trx_commit flag to the value of "2" instead
    of its default value of "1" means that the underlying MySQL/MariaDB engine
    will no longer flush transactions to disk on a per-transaction basis;
    instead, flushes occur once per second.   This leads to far fewer
    disk writes and can dramatically improve write performance, at the cost
    of durability (e.g. will lose the last second's worth of transactions)
    if the database engine is ungracefully shut down.   The
    clustered nature of Galera mitigates this risk in that transactions
    are replicated to other nodes before completion, and the setting of
    "2" is considered to be generally safe for a Galera cluster, with the
    exception case of simultaneous power loss for all nodes.
lass="p">,2004 Eric Biederman (ebiederm@xmission.com) * Copyright (C) 2014 Red Hat Inc. * Author(s): Vivek Goyal <vgoyal@redhat.com> * * This code has been taken from kexec-tools. * * This source code is licensed under the GNU General Public License, * Version 2. See the file COPYING for more details. */ .text .balign 16 .code64 .globl entry64, entry64_regs entry64: /* Setup a gdt that should be preserved */ lgdt gdt(%rip) /* load the data segments */ movl $0x18, %eax /* data segment */ movl %eax, %ds movl %eax, %es movl %eax, %ss movl %eax, %fs movl %eax, %gs /* Setup new stack */ leaq stack_init(%rip), %rsp pushq $0x10 /* CS */ leaq new_cs_exit(%rip), %rax pushq %rax lretq new_cs_exit: /* Load the registers */ movq rax(%rip), %rax movq rbx(%rip), %rbx movq rcx(%rip), %rcx movq rdx(%rip), %rdx movq rsi(%rip), %rsi movq rdi(%rip), %rdi movq rsp(%rip), %rsp movq rbp(%rip), %rbp movq r8(%rip), %r8 movq r9(%rip), %r9 movq r10(%rip), %r10 movq r11(%rip), %r11 movq r12(%rip), %r12 movq r13(%rip), %r13 movq r14(%rip), %r14 movq r15(%rip), %r15 /* Jump to the new code... */ jmpq *rip(%rip) .section ".rodata" .balign 4 entry64_regs: rax: .quad 0x0 rcx: .quad 0x0 rdx: .quad 0x0 rbx: .quad 0x0 rsp: .quad 0x0 rbp: .quad 0x0 rsi: .quad 0x0 rdi: .quad 0x0 r8: .quad 0x0 r9: .quad 0x0 r10: .quad 0x0 r11: .quad 0x0 r12: .quad 0x0 r13: .quad 0x0 r14: .quad 0x0 r15: .quad 0x0 rip: .quad 0x0 .size entry64_regs, . - entry64_regs /* GDT */ .section ".rodata" .balign 16 gdt: /* 0x00 unusable segment * 0x08 unused * so use them as gdt ptr */ .word gdt_end - gdt - 1 .quad gdt .word 0, 0, 0 /* 0x10 4GB flat code segment */ .word 0xFFFF, 0x0000, 0x9A00, 0x00AF /* 0x18 4GB flat data segment */ .word 0xFFFF, 0x0000, 0x9200, 0x00CF gdt_end: stack: .quad 0, 0 stack_init: