Date: Mon, 30 Nov 2015 01:44:31 +0000 (GMT) From: jenkins-admin@FreeBSD.org To: mckusick@FreeBSD.org, dim@FreeBSD.org, jenkins-admin@FreeBSD.org, freebsd-current@FreeBSD.org Subject: FreeBSD_HEAD - Build #3589 - Fixed Message-ID: <1119240898.273.1448847873517.JavaMail.jenkins@jenkins-9.freebsd.org> In-Reply-To: <324754440.265.1448833900182.JavaMail.jenkins@jenkins-9.freebsd.org> References: <324754440.265.1448833900182.JavaMail.jenkins@jenkins-9.freebsd.org>
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FreeBSD_HEAD - Build #3589 - Fixed: Build information: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD/3589/ Full change log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD/3589/changes Full build log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD/3589/console Change summaries: 291461 by dim: Fix buildworld after r291453, similar to r284346: url->user and url->pwd are arrays, so they can never be NULL. Reported by: many Pointy hat to: des 291460 by mckusick: As the kernel allocates and frees vnodes, it fully initializes them on every allocation and fully releases them on every free. These are not trivial costs: it starts by zeroing a large structure then initializes a mutex, a lock manager lock, an rw lock, four lists, and six pointers. And looking at vfs.vnodes_created, these operations are being done millions of times an hour on a busy machine. As a performance optimization, this code update uses the uma_init and uma_fini routines to do these initializations and cleanups only as the vnodes enter and leave the vnode_zone. With this change the initializations are only done kern.maxvnodes times at system startup and then only rarely again. The frees are done only if the vnode_zone shrinks which never happens in practice. For those curious about the avoided work, look at the vnode_init() and vnode_fini() functions in kern/vfs_subr.c to see the code that has been removed from the main vnode allocation/free path. Reviewed by: kib Tested by: Peter Holm
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