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<p>as far as I understand, if a file gets hot again, there is no
rule for putting the file back into a faster storage device? <br>
</p>
<p>We would like having something like a storage elevator depending
on the fileheat.<br>
</p>
<p>In our setup, customer likes to migrate/move data even when the
the threshold is not hit, just because it's cold and the price of
the storage is less.<br>
</p>
<br>
<div class="moz-cite-prefix">On 27.09.2016 16:25, Marc A Kaplan
wrote:<br>
</div>
<blockquote
cite="mid:OF23748E4B.330E0723-ON8525803B.004D3562-8525803B.004F34EB@notes.na.collabserv.com"
type="cite"><tt><font size="2"><br>
You asked ... "We are wishing to migrate data according to
the
heat onto different <br>
storage categories (expensive --> cheap devices)"</font></tt><br>
<br>
<br>
<tt><font size="2">We suggest a policy rule like this:</font></tt><br>
<br>
<tt><font size="2">Rule 'm' Migrate From Pool 'Expensive' To Pool
'Thrifty' Threshold(90,75) Weight(-FILE_HEAT) /* minus sign!
*/</font></tt><br>
<br>
<br>
<tt><font size="2">Which you can interpret as:</font></tt><br>
<br>
<tt><font size="2">When The 'Expensive' pool is 90% or more full,
Migrate
the lowest heat (coldest!) files to pool 'Thrifty', until</font></tt><br>
<tt><font size="2">the occupancy of 'Expensive' has been reduced
to 75%.</font></tt><br>
<br>
<tt><font size="2">The concepts of Threshold and Weight have been
in
the produce since the MIGRATE rule was introduced.</font></tt><br>
<br>
<tt><font size="2">Another concept we introduced at the same time
as
FILE_HEAT was GROUP POOL. We've had little feedback and very</font></tt><br>
<tt><font size="2">few questions about this, so either it works
great
or is not being used much. (Maybe both are true ;-) )</font></tt><br>
<br>
<tt><font size="2">GROUP POOL migration is documented in the
Information
Lifecycle Management chapter along with the other elements of
the policy
rules.</font></tt><br>
<br>
<tt><font size="2">In the 4.2.1 doc we suggest you can "repack"
several pools with one GROUP POOL rule and one MIGRATE rule
like this:</font></tt><br>
<br>
<font face="Palatino-Roman" size="2">You can “repack” a group pool
by </font><font face="Palatino-Bold" size="2"><b>WEIGHT</b></font><font
face="Palatino-Roman" size="2">.
Migrate files of higher weight to preferred disk pools</font><br>
<font face="Palatino-Roman" size="2">by specifying a group pool as
both
the source and the target of a </font><font
face="Palatino-Bold" size="2"><b>MIGRATE
</b></font><font face="Palatino-Roman" size="2">rule.</font><br>
<br>
<font face="BookMaster" size="1">rule ’grpdef’ GROUP POOL ’gpool’
IS ’ssd’ LIMIT(90) THEN ’fast’ LIMIT(85) THEN ’sata’</font><br>
<font face="BookMaster" size="1">rule ’repack’ MIGRATE FROM POOL
’gpool’
TO POOL ’gpool’ WEIGHT(FILE_HEAT)</font><br>
<br>
<br>
<tt><font size="2">This should rank all the files in the three
pools
from hottest to coldest, and migrate them </font></tt><br>
<tt><font size="2">as necessary (if feasible) so that 'ssd' is up
to
90% full of the hottest, 'fast' is up to 85% full of the next</font></tt><br>
<tt><font size="2">most hot, and the coolest files will be
migrated to
'sata'.</font></tt><br>
<tt><font size="2"><br>
<br>
</font></tt><br>
<br>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Andreas Landhäußer +49 151 12133027 (mobile)
<a class="moz-txt-link-abbreviated" href="mailto:alandhae@gmx.de">alandhae@gmx.de</a>
</pre>
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