Help Understanding Output and question about /dev/ Post: 302332575

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Top Forums UNIX for Dummies Questions & Answers Help Understanding Output and question about /dev/ Post 302332575 by pludi on Thursday 9th of July 2009 01:17:57 PM

07-09-2009

Registered User

For future reference, please use [code][/code] tags for listings, source code, ...

Quote:

Originally Posted by mojoman

Code:

Disk /dev/sda: 17849 cylinders, 255 heads, 63 sectors/track
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start     End   #cyls    #blocks   Id  System
/dev/sda1   *      0+    499     500-   4016218+  83  Linux
/dev/sda2        500     999     500    4016250   82  Linux swap / Solaris
/dev/sda3       1000   17848   16849  135339592+  83  Linux
/dev/sda4          0       -       0          0    0  Empty

This means that each of the 500 cylinders allocated for /dev/sda2 is 8225280 bytes (or about 8MB) large, which is about 4GB in total. Or, from the next column, it consists of 4016250 blocks � 1024 bytes = ~4GB.

You can specify the intended size by using '+1024M' (=1GB) when fdisk asks for the ending block number.

Quote:

Originally Posted by mojoman

One other question:
/dev/shm 517172 0 517172 0% /dev/shm

Is /dev/shm the swap partition /dev/sda2?

No, it's a pseudo filesystem (much like /dev, /proc, /sys) used for shared memory usage (IPC/Message passing). Swap partitions don't show up in the output of mount/df. Use swapon -s for that.

pludi

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