저널링 옵션과 쓰기 레이턴시(write latency) 테스트
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/dev/sdb7 on /snapshot type ext3 (rw,data=writeback)
[root@yum /]# time dd if=/dev/zero of=/snapshot/testfile bs=1024 count=2048000(write a 2Gfile)
2048000+0개의 레코드를 입력하였습니다
2048000+0개의 레코드를 출력하였습니다
real 0m52.466s
user 0m0.288s
sys 0m7.816s
[root@yum snapshot]# time cat testfile (when test file was 20M file)
real 0m14.482s
user 0m0.004s
sys 0m0.100s
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/dev/sdb7 on /snapshot type ext3 (rw,data=ordered)
[root@yum /]# time dd if=/dev/zero of=/snapshot/testfile bs=1024 count=2048000(write a 2Gfile)
2048000+0개의 레코드를 입력하였습니다
2048000+0개의 레코드를 출력하였습니다
real 0m58.093s
user 0m0.308s
sys 0m8.521s
[root@yum snapshot]# time cat testfile(when test file was 20M file)
real 0m14.630s
user 0m0.000s
sys 0m0.108s
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/dev/sdb7 on /snapshot type ext3 (rw,data=journal)
[root@yum /]# time dd if=/dev/zero of=/snapshot/testfile bs=1024 count=2048000(write a 2Gfile)
2048000+0개의 레코드를 입력하였습니다
2048000+0개의 레코드를 출력하였습니다
real 2m0.996s
user 0m0.272s
sys 0m8.805s
[root@yum snapshot]# time cat testfile(when test file was 20M file)
real 0m14.275s
user 0m0.000s
sys 0m0.120s
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* 참고링크: http://www.ibm.com/developerworks/kr/library/l-fs8.html