Date: Fri, 10 Aug 2018 09:15:22 +0200 From: "Patrick M. Hausen" <hausen@punkt.de> To: Mark Johnston <markj@freebsd.org> Cc: freebsd-virtualization@freebsd.org, freebsd-dtrace@freebsd.org Subject: Re: Why can't I dtrace processes running in a jail from the host? Message-ID: <8B1BDE9F-BDAD-4CEB-B7A2-8052497F50EA@punkt.de> In-Reply-To: <20180809145258.GA68459@raichu> References: <FB08F1C9-C066-4C78-8D35-E2A522ADC8F8@punkt.de> <20180809145258.GA68459@raichu>
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Hi! > Am 09.08.2018 um 16:52 schrieb Mark Johnston <markj@freebsd.org>: > For userland static probes to be globally visible, the process needs to > register them with the kernel when it starts. This is done > automatically using a constructor which issues ioctls to > /dev/dtrace/helper, hence the requirement for /dev/dtrace/* in the jail. I figured as much. Enabling /dev/dtrace/* in the jail and restarting the jail made the probes visible in the host system I'm still somewhat stuck. What I'm trying to do is track down some performance problems in a large complex PHP web application. I have done this in the past on "regular" setups without jails and with PHP 5.6 compiled with dtrace support using /usr/local/share/dtrace-toolkit/Php/* ... This setup is jailed with PHP 7.2, dtrace support seems to be the default for the port. I'm specifically after php-fpm dtrace_execute_ex function-entry php-fpm dtrace_execute_ex function-return of course, to see where the application spends it's CPU cycles. But regardless if I'm doing this on the host or in the jail, I only get these results: dtrace -m php\* ZEND_CATCH_SPEC_CONST_CV_HANDLER:exception-caught php_request_shutdown:request-shutdown php_request_startup:request-startup zend_error:error zend_throw_exception_internal:exception-thrown Nothing else. Still `dtrace -m php\* -l` does show all the probes. Any ideas? Thanks Patrick -- punkt.de GmbH Internet - Dienstleistungen - Beratung Kaiserallee 13a Tel.: 0721 9109-0 Fax: -100 76133 Karlsruhe info@punkt.de http://punkt.de AG Mannheim 108285 Gf: Juergen Egeling
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