<div dir="ltr"><div><snip></div><div> <br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div>
    Maybe there are ways to rearrange the initialization order so that
    sub-systems that need to perform particular memory area reservation
    can be done before we reserve the heap? FWIW, ZGC can reserve
    discontiguous memory (See:
    ZVirtualMemoryManager::reserve_discontiguous) and can deal with
    memory areas being pre-reserved by other sub-systems.<br>
    <br></div></blockquote><div><br></div><div>No, I think the current order makes sense. For GCs that use compressed oops and therefore benefit from having "good" heap ranges, GC reservation should come first since the benefit of zero-based compressed oops is larger than the one from zero-based narrow Klasses.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div>
    StefanK<br>
    <br>
    <blockquote type="cite">
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        <div class="gmail_quote">
          <div> </div>
          <blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">If not, and we really
            need to add this to <br>
            CollectedHeap for some reason, then I think reserved_range
            need to be <br>
            renamed to something that is bleeding obvious not going to
            be available <br>
            for all GCs.<br>
            <br>
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            StefanK<br>
            <br>
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          <div>Thomas<br>
          </div>
          <div> </div>
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            ><br>
            > -------------<br>
            ><br>
            > PR Comment: <a href="https://git.openjdk.org/jdk/pull/14595#issuecomment-1604898333" rel="noreferrer" target="_blank">https://git.openjdk.org/jdk/pull/14595#issuecomment-1604898333</a><br>
            <br>
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    <br>
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