Partitioning Tips and Tricks - Revision history

Sidetone: /* Using RAM virtual file systems */

2018-02-11T05:09:38Z

Using RAM virtual file systems

Sidetone: /* Using RAM virtual file systems */ clarify mdmfs; tmpfs is suitable for desktops

2018-02-11T05:07:23Z

Using RAM virtual file systems: clarify mdmfs; tmpfs is suitable for desktops

Sidetone: /* Using RAM virtual file systems */

2015-11-01T08:34:43Z

Using RAM virtual file systems

Sidetone at 20:29, 30 October 2015

2015-10-30T20:29:53Z

Sidetone: /* Use soft links to your advantage! */

2015-10-30T20:26:35Z

Use soft links to your advantage!

Sidetone: /* Getting Hard Disk Information */

2015-10-30T20:24:08Z

Getting Hard Disk Information

Sidetone at 20:22, 30 October 2015

2015-10-30T20:22:25Z

Sidetone: virtual /var filesystem

2015-10-30T20:19:21Z

virtual /var filesystem

Sidetone: /* Using RAM for virtual files */

2015-10-30T13:42:52Z

Using RAM for virtual files

Sidetone at 13:42, 30 October 2015

2015-10-30T13:42:37Z

@@ Line 15: / Line 15: @@
 ==Using RAM virtual file systems==
-Here are instructions on how to use RAM as {{file|/tmp}} (temporary) or {{file|/var}} file systems. {{man|tmpfs|5}} is suitable for desktops, because it automatically adjust its file size, unlike {{man|mdmfs|8}}.
+Here are instructions on how to use RAM as {{file|/tmp}} (temporary) or {{file|/var}} file systems. {{man|tmpfs|5}} is suitable for desktops, because it automatically adjusts its file size, unlike {{man|mdmfs|8}}.
 To set up a {{man|tmpfs|5}} filesystem, enter into {{file|/etc/fstab}}:

@@ Line 15: / Line 15: @@
 ==Using RAM virtual file systems==
-Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Using the {{man|md|4}} driver, add the following, or similar variable to {{file|/etc/rc.conf}}:
+Here are instructions on how to use RAM as {{file|/tmp}} (temporary) or {{file|/var}} file systems. {{man|tmpfs|5}} is suitable for desktops, because it automatically adjust its file size, unlike {{man|mdmfs|8}}.
   tmpmfs="YES"
   tmpsize="3g"
-{{file|/var}} can also be put on ram, but this is only for operating systems that are read-only. On regular installs files in {{file|/var}} are needed for the operating system to resume normally, which would be flushed on a virtual {{file|/var}} file system.
+{{man|mdmfs|8}} can also be mounted through {{file|/etc/fstab}}:
   varmfs="YES"
   varmfs="512m"
 Virtual RAM filesystem are shared with harddrive swapspace to add capacity. There must be enough combined swap and RAM capacity to contain the virtual filesystem. .iso images can be mounted on swap too. See also ''[[mdconfig]]'' and related filesystem ram manpages for more information.

@@ Line 15: / Line 15: @@
 ==Using RAM virtual file systems==
-Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Using the {{man|md(4)}} driver, add the following, or similar variable to {{file|/etc/rc.conf}}:
+Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Using the {{man|md|4}} driver, add the following, or similar variable to {{file|/etc/rc.conf}}:
   tmpmfs="YES"
   tmpsize="3g"
@@ Line 23: / Line 23: @@
   varmfs="512m"
-{{man|mdmfs(8)}} and alternately {{man|tmpfs(5)}} file systems can also be mounted through {{file|/etc/fstab}}:
+{{man|mdmfs|8}} and alternately {{man|tmpfs|5}} file systems can also be mounted through {{file|/etc/fstab}}:
   md     ''/mydir1''     mfs     rw,-s1g     0 0
   tmpfs  ''/mydir2''     tmpfs   rw,-s1g     0 0

@@ Line 14: / Line 14: @@
 NOTE: as always, the ''best'' way to speed up swap is not to need it in the first place - if you've got heavy swap partition activity, and you can possibly afford to do it, add more RAM.  No matter ''what'' you do with your swap partition(s), accessing them is always going to be an order of magnitude or three slower than staying in RAM.
-==Using RAM for virtual files==
+==Using RAM virtual file systems==
 Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Using the {{man|md(4)}} driver, add the following, or similar variable to {{file|/etc/rc.conf}}:
   tmpmfs="YES"

@@ Line 5: / Line 5: @@
 ==Use soft links to your advantage!==
-Don't forget that you can use [[ln]] to do really nifty things with your drives and partitions.  For example if you've made a too small {{file|/usr}} partition and a very large {{file|''/data''}} partition, you might want to move the ports tree - which can occupy several gigs of space if you build lots of ports and aren't meticulous about cleaning out old distfiles and work directories - into the larger {{file|''/data''}} partition.  But instead of trying to laboriously fix the entire system so that it looks in {{file|''/data/ports''} instead of {{file|/usr/ports}}, what you can do instead is {{cmd|mv /usr/ports ''/data/''}} and then {{cmd|ln -s ''/data/ports'' /usr/ports}} - now it ''looks'' and ''works'' as though the ports tree is still in the default location, but in fact it's operating from the bigger partition!
+Don't forget that you can use [[ln]] to do really nifty things with your drives and partitions.  For example if you've made a too small {{file|/usr}} partition and a very large {{file|''/data''}} partition, you might want to move the ports tree - which can occupy several gigs of space if you build lots of ports and aren't meticulous about cleaning out old distfiles and work directories - into the larger {{file|''/data''}} partition.  But instead of trying to laboriously fix the entire system so that it looks in {{file|''/data/ports''}} instead of {{file|/usr/ports}}, what you can do instead is {{cmd|mv /usr/ports ''/data/''}} and then {{cmd|ln -s ''/data/ports'' /usr/ports}} - now it ''looks'' and ''works'' as though the ports tree is still in the default location, but in fact it's operating from the bigger partition!
 Another common use for this is {{file|/var/db}} on servers with large databases.  By default [[mysql]] places databases in {{file|/var/db}}, which is normally a very small partition (256MB or so) - and can be overwritten disturbingly quickly with apache logs and mailserver logs and the like, not to mention the databases themselves.  Rather than recompiling or reconfiguring the database server itself to look for its database in a different location, you can simply move the databases to a different partition and soft link to them, just as was described for the ports tree in the paragraph above.  Kill the database server, {{cmd|mv /var/db /data/db <nowiki>&&</nowiki> ln -s /data/db /var/db}} and restart the server with no conf changes necessary, and you're in business!

@@ Line 30: / Line 30: @@
 ==Getting Hard Disk Information==
-Sometimes you need information about the model or manufacturing numbers of drives that are in a running system. If the hard disk supports SMART (most do), you can use the {{cmd|smartctl}} utility (available from the {{port|sysutils/smartmontools}} [[ports tree | port]]) to extract the model numbers.  Running {{cmd|smartctl -i /dev/ad4}} as root on my system gives output like this:
+Sometimes you need information about the model or manufacturing numbers of drives that are in a running system. If the hard disk supports SMART (most do), you can use the {{cmd|smartctl}} utility (available from {{port|sysutils/smartmontools}}) to extract the model numbers.  Running {{cmd|smartctl -i /dev/ad4}} as root on my system gives output like this:
   === START OF INFORMATION SECTION ===
   Device Model:    WDC WD2500JB-00EVA0

@@ Line 2: / Line 2: @@
 ==Make yourself a tiny little partition for /mnt==
-If you plan to work with removable read-write filesystems - USB drives, IDE or SCSI removables, whatever - make yourself a teeny tiny (like 5 or 10 MB or less) partition for /mnt, and mount the devices to /mnt/removable or /mnt/usbdrive or what have you.  That way if a script or a command you run tries to copy a few gigs worth of data and you DON'T have your removable device properly mounted, it will fill your little throwaway /mnt partition that you don't really need (and do it very quickly), instead of you accidentally filling your root partition, which can cause system instabilities.
+If you plan to work with removable read-write filesystems - USB drives, IDE or SCSI removables, whatever - make yourself a teeny tiny (like 5 or 10 MB or less) partition for {{file|/mnt}}, and mount the devices to {{file|/mnt/''removable''}} or {{file|/mnt/''usbdrive''}} or what have you.  That way if a script or a command you run tries to copy a few gigs worth of data and you DON'T have your removable device properly mounted, it will fill your little throwaway {{file|/mnt}} partition that you don't really need (and do it very quickly), instead of you accidentally filling your root partition, which can cause system instabilities.
 ==Use soft links to your advantage!==
-Don't forget that you can use [[ln]] to do really nifty things with your drives and partitions.  For example if you've made a too small /usr partition and a very large /data partition, you might want to move the ports tree - which can occupy several gigs of space if you build lots of ports and aren't meticulous about cleaning out old distfiles and work directories - into the larger /data partition.  But instead of trying to laboriously fix the entire system so that it looks in /data/ports instead of /usr/ports, what you can do instead is '''mv /usr/ports /data/''' and then '''ln -s /data/ports /usr/ports''' - now it ''looks'' and ''works'' as though the ports tree is still in the default location, but in fact it's operating from the bigger partition!
+Don't forget that you can use [[ln]] to do really nifty things with your drives and partitions.  For example if you've made a too small {{file|/usr}} partition and a very large /data partition, you might want to move the ports tree - which can occupy several gigs of space if you build lots of ports and aren't meticulous about cleaning out old distfiles and work directories - into the larger {{file|''/data''}} partition.  But instead of trying to laboriously fix the entire system so that it looks in {{file|''/data/ports''} instead of {{file|/usr/ports}}, what you can do instead is {{cmd|mv /usr/ports ''/data/''}} and then {{cmd|ln -s ''/data/ports'' /usr/ports}} - now it ''looks'' and ''works'' as though the ports tree is still in the default location, but in fact it's operating from the bigger partition!
-Another common use for this is /var/db on servers with large databases.  By default [[mysql]] places databases in /var/db, which is normally a very small partition (256MB or so) - and can be overwritten disturbingly quickly with apache logs and mailserver logs and the like, not to mention the databases themselves.  Rather than recompiling or reconfiguring the database server itself to look for its database in a different location, you can simply move the databases to a different partition and soft link to them, just as was described for the ports tree in the paragraph above.  Kill the database server, '''mv /var/db /data/db && ln -s /data/db /var/db''' and restart the server with no conf changes necessary, and you're in business!
+Another common use for this is {{file|/var/db}} on servers with large databases.  By default [[mysql]] places databases in {{file|/var/db}}, which is normally a very small partition (256MB or so) - and can be overwritten disturbingly quickly with apache logs and mailserver logs and the like, not to mention the databases themselves.  Rather than recompiling or reconfiguring the database server itself to look for its database in a different location, you can simply move the databases to a different partition and soft link to them, just as was described for the ports tree in the paragraph above.  Kill the database server, {{cmd|mv /var/db /data/db <nowiki>&&</nowiki> ln -s /data/db /var/db}} and restart the server with no conf changes necessary, and you're in business!
 ==Multiple Disks? Multiple /swap==
-If you've got two or more disks, you'll speed up performance on them by creating swap partitions on both of them -- no more moving data through the system bus to page files from disk 1 to your swap partition on disk 0. Some folks recommend that swap always be the first slice on the disk (even before / or any other partitions) because it's supposed to increase read/write times for stuff in swap; I've never noticed any real difference when I've done this, but if you have a lot of read/write-intensive operations (big databases, for e.g.,) you may want to consider this.
+If you've got two or more disks, you'll speed up performance on them by creating swap partitions on both of them -- no more moving data through the system bus to page files from disk 1 to your swap partition on disk 0. Some folks recommend that swap always be the first slice on the disk (even before {{file|/}} or any other partitions) because it's supposed to increase read/write times for stuff in swap; I've never noticed any real difference when I've done this, but if you have a lot of read/write-intensive operations (big databases, for e.g.,) you may want to consider this.
 NOTE: as always, the ''best'' way to speed up swap is not to need it in the first place - if you've got heavy swap partition activity, and you can possibly afford to do it, add more RAM.  No matter ''what'' you do with your swap partition(s), accessing them is always going to be an order of magnitude or three slower than staying in RAM.
 ==Using RAM for virtual files==
-Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Add the following, or similar variable to {{file|/etc/rc.conf}}:
+Here is an instruction on how to use RAM as {{file|/tmp}} (temporary) file space. Using the {{man|md(4)}} driver, add the following, or similar variable to {{file|/etc/rc.conf}}:
-  # tmpmfs="YES"
+  tmpmfs="YES"
-  # tmpsize="1000m"
+  tmpsize="3g"
-This virtual filesystem is shared with harddrive swapspace to add capacity. It seems as if .iso images can be mounted on swap too. See the {{man|md(4)}}, {{man|mdmfs(8)}} ''[[mdconfig]]'' and related manpages for more information.
 ==Getting Hard Disk Information==