Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.albasani.net!.POSTED!not-for-mail From: Jan Burse Newsgroups: comp.lang.java.programmer Subject: Re: Bulk Array Element Allocation, is it faster? Date: Sun, 25 Sep 2011 19:41:29 +0200 Organization: albasani.net Lines: 34 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: news.albasani.net p8AMIcOIDtJtf/aMb+mbfc2MnRRqCXQ8gVA4Ss0PMFhCqsEbyPy6VkIaj/5NP/ym+ErH591AzOzcZTuOBvA4XQ== NNTP-Posting-Date: Sun, 25 Sep 2011 17:41:30 +0000 (UTC) Injection-Info: news.albasani.net; logging-data="kk+MsPuGMJNKA/nNDf1nFyTz0o1omhyQGdC1J3jh5e845cxmSePyQT9cHmOC9BIrhkkoC2FudqxesXIPiL3toydtmewdEN9b+yye9w9vb0z6iUqvz0wgbbqXnZmV4uGn"; mail-complaints-to="abuse@albasani.net" User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0.2) Gecko/20110902 Firefox/6.0.2 SeaMonkey/2.3.3 In-Reply-To: Cancel-Lock: sha1:dz//I0Yq6tKm8blsbmrGCPCz/aI= Xref: x330-a1.tempe.blueboxinc.net comp.lang.java.programmer:8300 Jan Burse schrieb: > "I just wonder wether modern JIT do optimize > Code of the following form:" > > Please focus on that. Focus is also on JIT and not on JVM. So more on compilation techniques than on execution techniques (where draw the line?). Answer could be balantly that JIT does nothing, and then it must be something in the JVM. Andreas Leitgreb; > I understand perfectly well, that you *were* resorting > to those assumptions when you first noticed the effect, > but after Patricia's and others' answers I wouldn't > expect those assumptions to be still necessary to > explain your observations. But when the JIT would do something, then it is not necessary that the JVM does something, and would be a technique that also works on old CPUs without pipelining super cache whatever. I did not not yet have time to test the phaenomen on old CPU. Probably when I switch to old CPUs and also old JDKs I will also end up with old JITs. Anyway would be interested into JIT insights old and new. Bye