RFR (M): 8077144: Concurrent mark initialization takes too long (original) (raw)

Thomas Schatzl thomas.schatzl at oracle.com
Thu Mar 31 09:49:13 UTC 2016

Hi Kim,

On Tue, 2016-03-29 at 20:41 -0400, Kim Barrett wrote:

> On Mar 29, 2016, at 5:06 AM, Thomas Schatzl <_ _> thomas.schatzl at oracle.com> wrote: > > Hi, > > On Fri, 2016-03-25 at 21:48 -0400, Kim Barrett wrote: > > > On Mar 25, 2016, at 9:38 PM, Kim Barrett <_ _> > > kim.barrett at oracle.com> > > > wrote: > > > > > > > On Mar 15, 2016, at 6:12 PM, Thomas Schatzl <_ _> > > > thomas.schatzl at oracle.com> wrote: > > > > > > > > Hi Mikael, > > > > > > > > updated webrev at > > > > http://cr.openjdk.java.net/~tschatzl/8077144/webrev.3/ (full) > > > > http://cr.openjdk.java.net/~tschatzl/8077144/webrev.2to3/ ( > > > > diff > > > > ) > > > > > > > > which implements the suggested changes. > > > > > > src/share/vm/utilities/bitMap.hpp > > > 147 static idxt sizeinwords(sizet sizeinbits) { > > > > > > I find the name of this function confusing in conjunction with > > > the > > > no-arg ordinary member function; I'm not keen on overloads with > > > with > > > very different semantics and usage. Clearer (to me) here might > > > be > > > something like calcsizeinwords. > > > > The existing BitMap::wordalignup could be used instead of > > introducing this new function. > > I am not sure if that function helps in an as concise way as > calcsizeinwords(). > > I.e. do you suggest to use wordalignup(size())? Then I could as > well > use sizeinbytes() and divide by sizeof(bmwordt). (by other > alignment/size constraints a per-region part must always be word > -aligned). > > There has been a particular (non-public) request to be specific > with > sizes in these changes. > > Or do you mean, use wordalignup() in calcsizeinwords()?

When I mentioned wordalignup, I was thinking there was a bits per bmwordt constant somewhere that could be used to get the word size after aligning up. But there doesn’t seem to be any such thing, so ignore that part of the suggestion. So I would like a different name, rather than overloading sizeinwords. calcsizeinwords would be fine, or something else if you have a better suggestion. Other than this, with the deferral of other issues to JDK-8151386, looks good. I don’t need a new webrev for a name change here.

Thanks for your review.

Thomas

More information about the hotspot-gc-dev mailing list