From: Eric Bollengier <eric@eb.homelinux.org>
Date: Fri, 4 Sep 2009 13:20:18 +0000 (+0000)
Subject: Add notes about new btape speed command
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=86bb823dd32efd7569b7dd660d491063df5ef98f;p=bacula%2Fdocs

Add notes about new btape speed command
---

diff --git a/docs/manuals/en/concepts/newfeatures.tex b/docs/manuals/en/concepts/newfeatures.tex
index a030bd87..62c06e9f 100644
--- a/docs/manuals/en/concepts/newfeatures.tex
+++ b/docs/manuals/en/concepts/newfeatures.tex
@@ -113,6 +113,49 @@ data that will be displayed.
 * .lsdir path=/ jobid=1,2
 \end{verbatim}
 
+\section{Testing your tape drive}
+\label{sec:btapespeed}
+
+To determine the best configuration of your tape drive, you can run the new
+\texttt{speed} command available in \texttt{btape}.
+
+This command can have the following arguments:
+\begin{itemize}
+\item[\texttt{file\_size=n}] Specify the Maximum File Size for this test
+  (between 1 and 5GB). This counter is in GB.
+\item[\texttt{nb\_file=n}] Specify the number of file to be written. The amount
+  of data should be greater than your memory ($file\_size*nb\_file$).
+\item[\texttt{skip\_zero}] This flag permits to skip tests with constant
+  data.
+\item[\texttt{skip\_random}] This flag permits to skip tests with random
+  data.
+\item[\texttt{skip\_raw}] This flag permits to skip tests with raw access.
+\item[\texttt{skip\_block}] This flag permits to skip tests with Bacula block
+  access.
+\end{itemize}
+
+\begin{verbatim}
+*speed file_size=3 skip_raw
+btape.c:1078 Test with zero data and bacula block structure.
+btape.c:956 Begin writing 3 files of 3.221 GB with blocks of 129024 bytes.
+++++++++++++++++++++++++++++++++++++++++++
+btape.c:604 Wrote 1 EOF to "Drive-0" (/dev/nst0)
+btape.c:406 Volume bytes=3.221 GB. Write rate = 44128.0 KB/s
++++++++++++++++++++++++++++++++++++++++++++
+btape.c:604 Wrote 1 EOF to "Drive-0" (/dev/nst0)
+btape.c:406 Volume bytes=3.221 GB. Write rate = 42951.2 KB/s
++++++++++++++++++++++++++++++++++++++++++++
+btape.c:604 Wrote 1 EOF to "Drive-0" (/dev/nst0)
+btape.c:406 Volume bytes=3.221 GB. Write rate = 43531.7 KB/s
+btape.c:383 Total Volume bytes=9.664 GB. Total Write rate = 43531.7 KB/s
+\end{verbatim}
+
+When using compression, the random test will give your the minimum throughput
+of your drive . The test using constant string will give you the maximum speed
+of your hardware chain. (cpu, memory, scsi card, cable, drive, tape).
+
+You can change the block size in the Storage Daemon configuration file.
+
 \section{Bat new features}
 
 \subsection{Media information view}