X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;ds=sidebyside;f=fio.1;h=d64fbb7ab5e0832f61f167d7fe2b20872f9ec2c1;hb=e3b4e568b362ec8d89243609e75763b37cf81b17;hp=5291126401a34fdd836137cc9694dc7b5574255d;hpb=69bdd6badc47775443413405e1aea4abe9e570c9;p=fio.git diff --git a/fio.1 b/fio.1 index 52911264..d64fbb7a 100644 --- a/fio.1 +++ b/fio.1 @@ -478,7 +478,15 @@ size, fio can alternate random and zeroed data throughout the IO buffer. If set, fio will fill the IO buffers with this pattern. If not set, the contents of IO buffers is defined by the other options related to buffer contents. The setting can be any pattern of bytes, and can be prefixed with 0x for hex -values. +values. It may also be a string, where the string must then be wrapped with +"". +.TP +.BI dedupe_percentage \fR=\fPint +If set, fio will generate this percentage of identical buffers when writing. +These buffers will be naturally dedupable. The contents of the buffers depend +on what other buffer compression settings have been set. It's possible to have +the individual buffers either fully compressible, or not at all. This option +only controls the distribution of unique buffers. .TP .BI nrfiles \fR=\fPint Number of files to use for this job. Default: 1. @@ -612,6 +620,17 @@ options. Using Glusterfs libgfapi async interface to direct access to Glusterfs volumes without having to go through FUSE. This ioengine defines engine specific options. +.TP +.B libhdfs +Read and write through Hadoop (HDFS). The \fBfilename\fR option is used to +specify host,port of the hdfs name-node to connect. This engine interprets +offsets a little differently. In HDFS, files once created cannot be modified. +So random writes are not possible. To imitate this, libhdfs engine expects +bunch of small files to be created over HDFS, and engine will randomly pick a +file out of those files based on the offset generated by fio backend. (see the +example job file to create such files, use rw=write option). Please note, you +might want to set necessary environment variables to work with hdfs/libhdfs +properly. .RE .P .RE @@ -668,7 +687,9 @@ Fio will normally perform IOs until it has exhausted the size of the region set by \fBsize\fR, or if it exhaust the allocated time (or hits an error condition). With this setting, the range/size can be set independently of the number of IOs to perform. When fio reaches this number, it will exit -normally and report status. +normally and report status. Note that this does not extend the amount +of IO that will be done, it will only stop fio if this condition is met +before other end-of-job criteria. .TP .BI fsync \fR=\fPint How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data. If