Re: [systemd-devel] Switch root slowness
Lennart Poettering lenn...@poettering.net writes: On Thu, 30.10.14 14:35, Lennart Poettering (lenn...@poettering.net) wrote: I wish there was a way how we could use getrandom() in a way like /dev/urandom, where we can pull out the non-initialized data anyway. In absence of that we can just fallback to /dev/urandom on EAGAIN I guess, and always pass GRND_NONBLOCK. I have now implemented that. Please test! Lennart It works now, thanks! -- Jan Synacek Software Engineer, Red Hat signature.asc Description: PGP signature ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] Switch root slowness
Hello, commit 539618a0ddc2dc7f0fbe28de2ae0e07b34c81e60 Author: Lennart Poettering lenn...@poettering.net Date: Wed Oct 29 17:06:32 2014 +0100 util: make use of the new getrandom() syscall if it is available when needing entropy Doesn't require an fd, and could be a bit faster, so let's make use of it, if it is available. Beginning from this commit, switch root takes about a minute on my machine. Excerpts from the journal: Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: random: systemd urandom read with 10 bits of entropy available Oct 30 13:08:37 fedora-rawhide-systemd-virt systemd-journal[109]: Journal started Oct 30 13:08:37 fedora-rawhide-systemd-virt dracut-cmdline[105]: dracut-22 (Rawhide) dracut-038-36.git20140815.fc22 Oct 30 13:08:37 fedora-rawhide-systemd-virt dracut-cmdline[105]: Using kernel command line parameters: Oct 30 13:08:37 fedora-rawhide-systemd-virt systemd-udevd[158]: starting version 216 This line is pretty weird too, this commit is after v217 had been tagged. Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Initialized drm 1.1.0 20060810 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Device Version 0.0 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Compression level 0 log level 0 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Currently using mode #0, list at 0x488 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] 12286 io pages at offset 0x100 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] 16777216 byte draw area at offset 0x0 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] RAM header offset: 0x3ffe000 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] rom modes offset 0x488 for 128 modes Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [TTM] Zone kernel: Available graphics memory: 1024780 kiB Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [TTM] Initializing pool allocator Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [TTM] Initializing DMA pool allocator Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] qxl: 16M of VRAM memory size Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] qxl: 63M of IO pages memory ready (VRAM domain) Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] qxl: 64M of Surface memory size Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] main mem slot 1 [f400,3ffe000] Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] surface mem slot 2 [f800,400] Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Supports vblank timestamp caching Rev 2 (21.10.2013). Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] No driver support for vblank timestamp query. Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] fb mappable at 0xF400, size 3145728 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] fb: depth 24, pitch 4096, width 1024, height 768 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: fbcon: qxldrmfb (fb0) is primary device Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: Console: switching to colour frame buffer device 128x48 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: qxl :00:02.0: fb0: qxldrmfb frame buffer device Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: qxl :00:02.0: registered panic notifier Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: [drm] Initialized qxl 0.1.0 20120117 for :00:02.0 on minor 0 Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: PM: Starting manual resume from disk Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: PM: Hibernation image partition 8:2 present Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: PM: Looking for hibernation image. Oct 30 13:08:37 fedora-rawhide-systemd-virt systemd-fsck[198]: /dev/sda3: clean, 83696/853440 files, 1149042/3410688 blocks Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: PM: Image not found (code -22) Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: PM: Hibernation image not present or could not be loaded. Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: EXT4-fs (sda3): mounted filesystem with ordered data mode. Opts: (null) Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd[1]: Switching root. Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd-journal[109]: Journal stopped Hangs here for a while with no output. Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journald[109]: Received SIGTERM from PID 1 (systemd). snip a lot of selinux related stuff Oct 30 13:09:44 fedora-rawhide-systemd-virt kernel: random:
Re: [systemd-devel] Switch root slowness
On Thu, Oct 30, 2014 at 01:18:24PM +0100, Jan Synáček wrote: Hello, commit 539618a0ddc2dc7f0fbe28de2ae0e07b34c81e60 Author: Lennart Poettering lenn...@poettering.net Date: Wed Oct 29 17:06:32 2014 +0100 util: make use of the new getrandom() syscall if it is available when needing entropy Doesn't require an fd, and could be a bit faster, so let's make use of it, if it is available. Beginning from this commit, switch root takes about a minute on my machine. Excerpts from the journal: Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: random: systemd urandom read with 10 bits of entropy available Oct 30 13:08:37 fedora-rawhide-systemd-virt systemd-journal[109]: Journal started Oct 30 13:08:37 fedora-rawhide-systemd-virt dracut-cmdline[105]: dracut-22 (Rawhide) dracut-038-36.git20140815.fc22 Oct 30 13:08:37 fedora-rawhide-systemd-virt dracut-cmdline[105]: Using kernel command line parameters: Oct 30 13:08:37 fedora-rawhide-systemd-virt systemd-udevd[158]: starting version 216 This line is pretty weird too, this commit is after v217 had been tagged. Not that weird, it just means you didn't update your initrd after updating to 217. ... Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd[1]: Switching root. Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd-journal[109]: Journal stopped Hangs here for a while with no output. Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journald[109]: Received SIGTERM from PID 1 (systemd). snip a lot of selinux related stuff Oct 30 13:09:44 fedora-rawhide-systemd-virt kernel: random: nonblocking pool is initialized Is anyone else running into this? Probably fixed by: http://cgit.freedesktop.org/systemd/systemd/commit/?id=74a550c5d8228 d ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Switch root slowness
On Thu, 30.10.14 13:18, Jan Synáček (jsyna...@redhat.com) wrote: Hello, commit 539618a0ddc2dc7f0fbe28de2ae0e07b34c81e60 Author: Lennart Poettering lenn...@poettering.net Date: Wed Oct 29 17:06:32 2014 +0100 util: make use of the new getrandom() syscall if it is available when needing entropy Doesn't require an fd, and could be a bit faster, so let's make use of it, if it is available. Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: EXT4-fs (sda3): mounted filesystem with ordered data mode. Opts: (null) Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd[1]: Switching root. Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd-journal[109]: Journal stopped Hangs here for a while with no output. Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journald[109]: Received SIGTERM from PID 1 (systemd). snip a lot of selinux related stuff Oct 30 13:09:44 fedora-rawhide-systemd-virt kernel: random: nonblocking pool is initialized Is anyone else running into this? This could be due to the blocking nature of getrandom() if little entropy is available. The call waits by default until the pool is initialized before returning, which is probably what your system is waiting on. I wish there was a way how we could use getrandom() in a way like /dev/urandom, where we can pull out the non-initialized data anyway. In absence of that we can just fallback to /dev/urandom on EAGAIN I guess, and always pass GRND_NONBLOCK. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Switch root slowness
El 30/10/14 a las #4, Lennart Poettering escribió: In absence of that we can just fallback to /dev/urandom on EAGAIN I guess, and always pass GRND_NONBLOCK. Before you made this commit, I had a local patch that did exactly that..currently this is the best solution. I suggest to give up on any failure (not implemented, blocking..whatever) and fallback to reading /dev/urandom. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Switch root slowness
Dave Reisner d...@falconindy.com writes: On Thu, Oct 30, 2014 at 01:18:24PM +0100, Jan Synáček wrote: Hello, commit 539618a0ddc2dc7f0fbe28de2ae0e07b34c81e60 Author: Lennart Poettering lenn...@poettering.net Date: Wed Oct 29 17:06:32 2014 +0100 util: make use of the new getrandom() syscall if it is available when needing entropy Doesn't require an fd, and could be a bit faster, so let's make use of it, if it is available. Beginning from this commit, switch root takes about a minute on my machine. ... Probably fixed by: http://cgit.freedesktop.org/systemd/systemd/commit/?id=74a550c5d8228 Nope, still slow. -- Jan Synacek Software Engineer, Red Hat signature.asc Description: PGP signature ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Switch root slowness
On Thu, 30.10.14 14:35, Lennart Poettering (lenn...@poettering.net) wrote: On Thu, 30.10.14 13:18, Jan Synáček (jsyna...@redhat.com) wrote: Hello, commit 539618a0ddc2dc7f0fbe28de2ae0e07b34c81e60 Author: Lennart Poettering lenn...@poettering.net Date: Wed Oct 29 17:06:32 2014 +0100 util: make use of the new getrandom() syscall if it is available when needing entropy Doesn't require an fd, and could be a bit faster, so let's make use of it, if it is available. Oct 30 13:08:37 fedora-rawhide-systemd-virt kernel: EXT4-fs (sda3): mounted filesystem with ordered data mode. Opts: (null) Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd[1]: Switching root. Oct 30 13:08:38 fedora-rawhide-systemd-virt systemd-journal[109]: Journal stopped Hangs here for a while with no output. Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journal[279]: Runtime journal is using 8.0M (max allowed 100.0M, trying to leave 150.1M free of 992.7M available → current limit 100.0M). Oct 30 13:09:44 fedora-rawhide-systemd-virt systemd-journald[109]: Received SIGTERM from PID 1 (systemd). snip a lot of selinux related stuff Oct 30 13:09:44 fedora-rawhide-systemd-virt kernel: random: nonblocking pool is initialized Is anyone else running into this? This could be due to the blocking nature of getrandom() if little entropy is available. The call waits by default until the pool is initialized before returning, which is probably what your system is waiting on. I wish there was a way how we could use getrandom() in a way like /dev/urandom, where we can pull out the non-initialized data anyway. In absence of that we can just fallback to /dev/urandom on EAGAIN I guess, and always pass GRND_NONBLOCK. I have now implemented that. Please test! Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
