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Is swap and Shared memory the same ?

 
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# 1  
Old 05-30-2013
Is swap and Shared memory the same ?
In Linux, Unix environments Is swap and Shared memory the same ?

In Linux, swap is mounted on /dev/shm ? I am wondering if the naming of 'shm' has anything to do with Shared memory ?
# 2  
Old 05-30-2013
Quote:
Originally Posted by kraljic
In Linux, Unix environments Is swap and Shared memory the same ?
Absolutely not.

Quote:
In Linux, swap is mounted on /dev/shm ? I am wondering if the naming of 'shm' has anything to do with Shared memory ?
Humm, which version of Linux are you seeing this on? Normally swap is backed by a backing store, i.e a disk partition. Are you using a Linux LiveCD?
This User Gave Thanks to fpmurphy For This Post:
kraljic
# 3  
Old 05-30-2013
The output of the following commands would be helpful: "uname -a" and "mount"

Regards,
Alister
# 4  
Old 05-31-2013
Info you've asked for

Code:
# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 5.4 (Tikanga)

# uname -a
Linux stomper189 2.6.18-164.el5 #1 SMP Tue Aug 18 11:51:48 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux


# mount
/dev/mapper/rootvg-rootvol on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/mapper/rootvg-varvol on /var type ext3 (rw,nosuid)
/dev/mapper/rootvg-homevol on /home type ext3 (rw,nosuid)
/dev/mapper/rootvg-sharedvol on /shared type ext3 (rw,nosuid)
/dev/sda1 on /boot type ext3 (rw,nosuid)
tmpfs on /dev/shm type tmpfs (rw,nosuid)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
/dev/mapper/datavg-prodloadvol on /pkms/prod/load type ext3 (rw)
/dev/mapper/datavg-crmprodloadvol on /crm/prod/load type ext3 (rw)
/dev/mapper/datavg-dboraclevol on /db/oracle type ext3 (rw)
/dev/mapper/datavg-pkmsarchive on /pkms/pkmsdb/archive type ext3 (rw)
/dev/mapper/datavg-pkmssystem on /pkms/pkmsdb/system type ext3 (rw)
/dev/mapper/datavg-pkmstbsdata01 on /pkms/pkmsdb/dbs/tbs_data01 type ext3 (rw)
/dev/mapper/datavg-pkmstbsindexvol on /pkms/pkmsdb/dbs/tbs_index01 type ext3 (rw)
/dev/mapper/datavg-crmtbsdata01 on /crm/crmdb/dbs/tbs_data01 type ext3 (rw)
/dev/mapper/datavg-crmtbsindexvol on /crm/crmdb/dbs/tbs_index01 type ext3 (rw)
/dev/mapper/datavg-dbcontrolvol on /db/control type ext3 (rw)
/dev/mapper/datavg-dbadminvol on /db/admin type ext3 (rw)
/dev/mapper/datavg-dbredovol on /db/redo type ext3 (rw)
/dev/mapper/datavg-tempvol on /temp type ext3 (rw)
/dev/mapper/datavg-pkmsfivol on /data/pkmsfi type ext3 (rw)
/dev/mapper/datavg-pkmsd01vol on /pkms/d01 type ext3 (rw)
/dev/mapper/datavg-crmd01vol on /crm/d01 type ext3 (rw)
/dev/mapper/datavg-datacrmdfvol on /usr/oracle type ext3 (rw)

 
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