zram: Compressed RAM based block devices ---------------------------------------- * Introduction The zram module creates RAM based block devices named /dev/zram<id> (<id> = 0, 1, ...). Pages written to these disks are compressed and stored in memory itself. These disks allow very fast I/O and compression provides good amounts of memory savings. Some of the usecases include /tmp storage, use as swap disks, various caches under /var and maybe many more :) Statistics for individual zram devices are exported through sysfs nodes at /sys/block/zram<id>/ Kconfig required: CONFIG_ZRAM=y CONFIG_CRYPTO_LZ4=y CONFIG_ZPOOL=y CONFIG_ZSMALLOC=y ZRAM Testcases -------------- zram_lib.sh: create library with initialization/cleanup functions zram.sh: For sanity check of CONFIG_ZRAM and to run zram01 and zram02 Two functional tests: zram01 and zram02: zram01.sh: creates general purpose ram disks with ext4 filesystems zram02.sh: creates block device for swap Commands required for testing: - bc - dd - free - awk - mkswap - swapon - swapoff - mkfs/ mkfs.ext4 For more information please refer: kernel-source-tree/Documentation/blockdev/zram.txt ='master' selected='selected'>master</option> <option value='nds-private-remove'>nds-private-remove</option> <option value='packet-loop-back'>packet-loop-back</option> <option value='packet-rx-pump-back'>packet-rx-pump-back</option> </select> <input type='submit' value='switch'/></form></td></tr> <tr><td class='sub'>net-next plumbings</td><td class='sub right'>Tobias Klauser</td></tr></table> <table class='tabs'><tr><td> <a href='/cgit.cgi/linux/net-next.git/'>summary</a><a href='/cgit.cgi/linux/net-next.git/refs/?id=69973b830859bc6529a7a0468ba0d80ee5117826'>refs</a><a href='/cgit.cgi/linux/net-next.git/log/security'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/security?id=69973b830859bc6529a7a0468ba0d80ee5117826'>tree</a><a href='/cgit.cgi/linux/net-next.git/commit/security?id=69973b830859bc6529a7a0468ba0d80ee5117826'>commit</a><a class='active' href='/cgit.cgi/linux/net-next.git/diff/security?id=69973b830859bc6529a7a0468ba0d80ee5117826&id2=2e4333c14de06a333783d6812cf3c4998f78b0c8'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/security'> <input type='hidden' name='id' value='69973b830859bc6529a7a0468ba0d80ee5117826'/><input type='hidden' name='id2' value='2e4333c14de06a333783d6812cf3c4998f78b0c8'/><select name='qt'> <option value='grep'>log msg</option> <option value='author'>author</option> <option value='committer'>committer</option> <option value='range'>range</option> </select> <input class='txt' type='search' size='10' name='q' value=''/> <input type='submit' value='search'/> </form> </td></tr></table> <div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/diff/?id=69973b830859bc6529a7a0468ba0d80ee5117826&id2=2e4333c14de06a333783d6812cf3c4998f78b0c8'>root</a>/<a href='/cgit.cgi/linux/net-next.git/diff/security?id=69973b830859bc6529a7a0468ba0d80ee5117826&id2=2e4333c14de06a333783d6812cf3c4998f78b0c8'>security</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='69973b830859bc6529a7a0468ba0d80ee5117826'/><input type='hidden' name='id2' value='2e4333c14de06a333783d6812cf3c4998f78b0c8'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=69973b830859bc6529a7a0468ba0d80ee5117826&id2=2e4333c14de06a333783d6812cf3c4998f78b0c8'>Diffstat</a> (limited to 'security')</div><table summary='diffstat' class='diffstat'>