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<p>Hi, Amit,<br>
</p>
<p>IMO, there is no one size fits all. <br>
</p>
<p>Some considerations about the bigger region size:</p>
<p>Reduce the humongous objects. The humongous objects are allocated
in old gen. If they can not be collected during young gc, they can
fill up the old gen quickly without marking or full gc.</p>
<p>Less remember set to keep track of. <br>
</p>
<p>Bigger TLAB. This could be good or bad. With bigger tlab, threads
need less refill trip, but may waste more tlab space. It depends
on the objects size.<br>
</p>
<p>Possible bigger waste due to humongous objects (depends on the
size of the objects)</p>
<p>Possible end of region waste for allocation.</p>
<p>Maybe others have more comments.<br>
</p>
<p>Thanks</p>
<p>Jenny<br>
</p>
<br>
<div class="moz-cite-prefix">On 02/01/2017 05:54 AM, Amit Balode
wrote:<br>
</div>
<blockquote
cite="mid:CACoa2tVabLBVfM9X=jAkXwcqRPcypoOTwMW2B=4AxmBxatZRcw@mail.gmail.com"
type="cite">
<div dir="ltr">Hello, We have multiple applications running in
production where predicting size of the runtime object is kinda
tough and random. It could vary from 1KB to 25MB for different
applications. To not have too many lingering configs for
different applications, I am trying to come up with standard set
of configs which could be applicable to all applications. Some
applications do not exceed 10KB object size, so I could
definitely keep 2MB as region size for them. But I am wondering
what would be disadvantage of setting all applications to 32MB
region size regardless of how small the object is?
<div><br>
</div>
<div>Is it that fragmentation issues will happen more if you
have less regions? If so, will the fragmentation issue happen
only during humongous allocations? </div>
<div>In term of performance, will selection of size change
anything?<br clear="all">
<div><br>
</div>
-- <br>
<div class="gmail_signature" data-smartmail="gmail_signature">
<div>Thanks & Regards,</div>
Amit.Balode<br>
<br>
</div>
</div>
</div>
<br>
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