Tag Archives: file

alloc_sem of Ext4 block group

Posted on January 10, 2012 by admin

Yesterday Amir Goldstein sent me an email for a deadlock issue. I was in Chinese New Year vacation, could not have time to check the code (also I know I can not answer his question with ease). Thanks to Ted, … Continue reading →

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Random I/O — Is raw device always faster than file system ?

Posted on January 10, 2012 by admin

For some implementations of distributed file systems, like TFS [1], developers think storing data on raw device directly (e.g. /dev/sdb, /dev/sdc…) might be faster than on file systems. Their choice is reasonable, 1, Random I/O on large file cannot get … Continue reading →

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Linux: Find Out What Partition a File Belongs To

Posted on January 1, 2012 by admin

How do I find out that /users/f/foo/file.txt file belongs to a specific partition? How do I find out on what partition a file exits? The df command report file system disk space usage including file names and directory names. The … Continue reading →

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Tarball Delete ( remove ) File

Posted on September 25, 2011 by admin

How do I delete OR remove a single file from within a tar ball under Unix / Linux like operating systems? You can use the following syntax to delete a file from a tar ball:   tar –delete -f example.tar … Continue reading →

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Increasing httperf maximum number of open descriptors from 1024 to 65535

Posted on July 26, 2011 by admin

By default httperf on Linux compiles with 1024 open descriptors and that can be a problem when you plan to test high bandwidth and many concurrent connection web servers. For safety you can edit /etc/security/limits.conf however you will also need … Continue reading →

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