These changes are the raw update to linux-4.4.6-rt14. Kernel sources
[kvmfornfv.git] / kernel / tools / testing / selftests / zram / README
diff --git a/kernel/tools/testing/selftests/zram/README b/kernel/tools/testing/selftests/zram/README
new file mode 100644 (file)
index 0000000..eb17917
--- /dev/null
@@ -0,0 +1,40 @@
+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_ZRAM_LZ4_COMPRESS=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