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<refentry id="gfarm_environ.7">

<refentryinfo><date>10 Aug 2015</date></refentryinfo>

<refmeta>
<refentrytitle>gfarm_environ</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>Gfarm</refmiscinfo>
</refmeta>

<refnamediv id="name">
<refname>gfarm_environ</refname>
<refpurpose>environment variables for Gfarm</refpurpose>
</refnamediv>

<!-- body begins here -->

<refsect1 id="description"><title>DESCRIPTION</title>

<variablelist>

<varlistentry>
<term><token>COLUMNS</token></term>
<listitem>
<para>
Specifies terminal window width.
Note that this setting overrides the actual width.
</para>
<para>
This is currently only used by the gfls command, when its output is
terminal.
</para>
<para>For example,</para>
<literallayout format="linespecific" class="normal">
	COLUMNS=120
</literallayout>
</listitem>
</varlistentry>

<varlistentry>
<term><token>GFARM_CONFIG_FILE</token></term>
<listitem>
<para>
The file specified by this variable is used as additional setting for
Gfarm clients, instead of the .gfarm2rc file under the user's home directory.
The settings in this file overrides the settings in gfarm2.conf.
</para>
<para>For example,</para>
<literallayout format="linespecific" class="normal">
	GFARM_CONFIG_FILE=$HOME/.gfarm2rc.alt
</literallayout>
</listitem>
</varlistentry>

<varlistentry>
<term><token>GFARM_FLAGS</token></term>
<listitem>
<para>
Specifies flags which modify the behavior of gfarm clients.
There is a following flag for now.
</para>
  <variablelist>
    <varlistentry>
      <term><token>r</token></term>
      <listitem>
      <para>
      If gfarm clients are invoked on a filesystem node,
      the gfarm clients replicates files to local node,
      before accessing them.
      </para>
      </listitem>
    </varlistentry>
  </variablelist>
<para>For example,</para>
<literallayout format="linespecific" class="normal">
	GFARM_FLAGS=r
</literallayout>
</listitem>
</varlistentry>

<varlistentry>
<term><token>GLOBUS_GSSAPI_CIPHERS</token></term>
<listitem>
<para>
If you are using globus_gssapi_gsi since version 11.17
(globus_toolkit since version 6.0.1433193802),
you can specify cipher lists for gsi authenticated connections
by this variable.
</para>
<para>
Please refer to the ciphers manual of the OpenSSL 
(
<citerefentry><refentrytitle>openssl_ciphers</refentrytitle><manvolnum>1</manvolnum></citerefentry>
or
<citerefentry><refentrytitle>ciphers</refentrytitle><manvolnum>1</manvolnum></citerefentry>
)
for the available cipher lists.
</para>
<para>
On x86 CPUs which have AES-NI instruction set,
specifying AES128-GCM-SHA256 may increase communication speed by few percent
as a recompense for slight security decrease.
On x86 CPUs which do not have AES-NI instruction set,
specifying AES128-SHA may double communication speed
as a recompense for slight security decrease.
It's recommended to measure the gain of the communication speed
before actually using this option, because the performace gain
varies between CPUs.
There are some measurement results in 
<quote><citerefentry><refentrytitle>Network Transfer Speed Comparison by ciphers</refentrytitle></citerefentry></quote>
section of the Gfarm Users' Manual for reference.
</para>
<para>For example,</para>
<literallayout format="linespecific" class="normal">
	GLOBUS_GSSAPI_CIPHERS=AES128-GCM-SHA256
</literallayout>
</listitem>
</varlistentry>

</variablelist>

</refsect1>

<refsect1 id="see-also"><title>SEE ALSO</title>
<para>
  <citerefentry><refentrytitle>gfls</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  <citerefentry><refentrytitle>gfarm2.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  <citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
