{"issue":{"created_at":"2011-11-24T18:27:51Z","state":"open","updated_at":"2011-11-25T07:34:48Z","comments":1,"user":{"gravatar_id":"984e68287c499e1fcf7606a8e6698f03","id":82119,"url":"https://api.github.com/users/mpokrywka","login":"mpokrywka","avatar_url":"https://secure.gravatar.com/avatar/984e68287c499e1fcf7606a8e6698f03?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png"},"body":"Prevent problems similar to [issue 316](http://code.google.com/p/phusion-passenger/issues/detail?id=316)\r\n    [31029.489919]   ***************************************************************\r\n    [31029.489922]   ***************************************************************\r\n    [31029.489924]   ** WARNING: Currently emulating unsupported memory accesses  **\r\n    [31029.489927]   **          in /lib/tls glibc libraries. The emulation is    **\r\n    [31029.489930]   **          slow. To ensure full performance you should      **\r\n    [31029.489932]   **          install a 'xen-friendly' (nosegneg) version of   **\r\n    [31029.489935]   **          the library, or disable tls support by executing **\r\n    [31029.489937]   **          the following as root:                           **\r\n    [31029.489940]   **          mv /lib/tls /lib/tls.disabled                    **\r\n    [31029.489942]   ** Offending process: zzzzzzzz (pid=16229)                   **\r\n    [31029.489945]   ***************************************************************\r\n    [31029.489947]   ***************************************************************\r\n","assignee":null,"id":2344046,"pull_request":{"patch_url":"https://github.com/FooBarWidget/passenger/pull/33.patch","html_url":"https://github.com/FooBarWidget/passenger/pull/33","diff_url":"https://github.com/FooBarWidget/passenger/pull/33.diff"},"number":33,"labels":[],"title":"Add support for virtualized (xen) platforms (i.e. amazon ec2)","closed_at":null,"html_url":"https://github.com/FooBarWidget/passenger/issues/33","url":"https://api.github.com/repos/FooBarWidget/passenger/issues/33","milestone":null},"action":"created","comment":{"created_at":"2011-11-25T07:34:48Z","updated_at":"2011-11-25T07:34:48Z","user":{"gravatar_id":"77a628df0bd2917d09828dd225a2c0ce","id":819,"url":"https://api.github.com/users/FooBarWidget","login":"FooBarWidget","avatar_url":"https://secure.gravatar.com/avatar/77a628df0bd2917d09828dd225a2c0ce?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png"},"body":"Thanks for this patch. However I read this from http://cs.felk.cvut.cz/~vaclam1/linux/ucebna/k310/data/doc/howto-xen-and-gentoo-en.html:\r\n\r\n\"Some software, in particular the glibc TLS library, is implemented in a way that will conflict with how Xen uses segment registers to circumvent a limitation of 32-bit x86 hardware platforms, causing poor performance whilst carrying out certain operations under Xen. This will result in a ~50% performance penalty running multi-threaded applications. To fix this, you must compile your system with the '-mno-tls-direct-seg-refs' flag.\"\r\n\r\nSo this flag is only required on x86? You should add an extra check so that this flag is only enabled for x86 systems.\r\n\r\nAnd before we can merge your changes we need you to sign the contributor agreement at http://www.phusion.nl/forms/contributor_agreement\r\nCould you follow the instructions there?","id":2872022,"url":"https://api.github.com/repos/FooBarWidget/passenger/issues/comments/2872022"}}