Re: [chromium-dev] Thread naming
Traceline is a good way to see how this happens. We generally name all of the Chrome threads (base::Thread), but the system is allowed to create threads of its own. Loads of APIs create threads, along with the windows worker pool (which we make good use of to help reuse threads). For example, wininet can create it's own thread pools, etc. I did some work on cutting down the number of threads and thread creation times. In specific thread creation can contend the main UI thread because of holding the loader lock for DLLMain initialization, etc. Here is an older example of traceline output: http://deanm.github.com/misc/traceline/traceline.xml#startup-release.json You can easily see which threads are created, when, and the call stacks for what created them by hovering on the lines. -- dean On Thu, Dec 31, 2009 at 7:09 PM, Jim Roskind j...@chromium.org wrote: I'm pretty sure we name all the threads we can (or at least used to), I *think* the problem is worker threads in a thread pool, which are started up and shut down automatically, and aren't named (and don't have message loops). When I was doing the work to generate the internal page about:tasks, it was critical to have names on all the threads (that I could), as the data also shows what threads sent and received tasks. Jim On Thu, Dec 31, 2009 at 1:11 AM, Berend-Jan Wever skyli...@chromium.org wrote: If you do not care about the way threads are run inside a process in Chromium, you can stop reading now. Some of our threads are named, while others are not. See below cdb.exe output for a renderer process: 2:020:x86 ~ 1 Id: d98.1588 Suspend: 1 Teb: 7efd8000 Unfrozen Chrome_ChildIOThread . 20 Id: d98.1440 Suspend: 1 Teb: 7efdb000 Unfrozen Main Thread 21 Id: d98.10d4 Suspend: 1 Teb: 7ef4d000 Unfrozen 22 Id: d98.171c Suspend: 1 Teb: 7efd5000 Unfrozen 2:020:x86 ~21 s ntdll32!ZwWaitForMultipleObjects+0x15: 76fa99fd c21400 ret 14h 2:021:x86 kp ChildEBP RetAddr 0399fcd4 7702787d ntdll32!ZwWaitForMultipleObjects+0x15 0399fe68 750feccb ntdll32!TppWaiterpThread+0x328 0399fe74 76fdd24d kernel32!BaseThreadInitThunk+0xe 0399feb4 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0399fecc ntdll32!_RtlUserThreadStart+0x1b 2:021:x86 ~22 s ntdll32!NtWaitForWorkViaWorkerFactory+0x12: 76fab5ee c20800 ret 8 2:022:x86 kp ChildEBP RetAddr 0357f6ec 76f9b927 ntdll32!NtWaitForWorkViaWorkerFactory+0x12 0357f81c 750feccb ntdll32!TppWorkerThread+0x1f6 0357f828 76fdd24d kernel32!BaseThreadInitThunk+0xe 0357f868 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0357f880 ntdll32!_RtlUserThreadStart+0x1b What are these threads and why are they nameless? Did we create these threads at all? (They could have been created by plugins/detours/etc. that we have no control over.) It would be nice if we could name all threads, so you know what you're looking at. Thanks! BJ Berend-Jan SkyLined Wever skyli...@google.com -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev
Re: [chromium-dev] Thread naming
Just for the record - Tp prefix stands for Thread Pool, and Tpp for Thread Pool Private (function). So yes, these are threads created by the system. On Thu, Dec 31, 2009 at 10:09 AM, Jim Roskind j...@chromium.org wrote: I'm pretty sure we name all the threads we can (or at least used to), I *think* the problem is worker threads in a thread pool, which are started up and shut down automatically, and aren't named (and don't have message loops). When I was doing the work to generate the internal page about:tasks, it was critical to have names on all the threads (that I could), as the data also shows what threads sent and received tasks. Jim On Thu, Dec 31, 2009 at 1:11 AM, Berend-Jan Wever skyli...@chromium.org wrote: If you do not care about the way threads are run inside a process in Chromium, you can stop reading now. Some of our threads are named, while others are not. See below cdb.exe output for a renderer process: 2:020:x86 ~ 1 Id: d98.1588 Suspend: 1 Teb: 7efd8000 Unfrozen Chrome_ChildIOThread . 20 Id: d98.1440 Suspend: 1 Teb: 7efdb000 Unfrozen Main Thread 21 Id: d98.10d4 Suspend: 1 Teb: 7ef4d000 Unfrozen 22 Id: d98.171c Suspend: 1 Teb: 7efd5000 Unfrozen 2:020:x86 ~21 s ntdll32!ZwWaitForMultipleObjects+0x15: 76fa99fd c21400 ret 14h 2:021:x86 kp ChildEBP RetAddr 0399fcd4 7702787d ntdll32!ZwWaitForMultipleObjects+0x15 0399fe68 750feccb ntdll32!TppWaiterpThread+0x328 0399fe74 76fdd24d kernel32!BaseThreadInitThunk+0xe 0399feb4 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0399fecc ntdll32!_RtlUserThreadStart+0x1b 2:021:x86 ~22 s ntdll32!NtWaitForWorkViaWorkerFactory+0x12: 76fab5ee c20800 ret 8 2:022:x86 kp ChildEBP RetAddr 0357f6ec 76f9b927 ntdll32!NtWaitForWorkViaWorkerFactory+0x12 0357f81c 750feccb ntdll32!TppWorkerThread+0x1f6 0357f828 76fdd24d kernel32!BaseThreadInitThunk+0xe 0357f868 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0357f880 ntdll32!_RtlUserThreadStart+0x1b What are these threads and why are they nameless? Did we create these threads at all? (They could have been created by plugins/detours/etc. that we have no control over.) It would be nice if we could name all threads, so you know what you're looking at. Thanks! BJ Berend-Jan SkyLined Wever skyli...@google.com -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev
[chromium-dev] Thread naming
If you do not care about the way threads are run inside a process in Chromium, you can stop reading now. Some of our threads are named, while others are not. See below cdb.exe output for a renderer process: 2:020:x86 ~ 1 Id: d98.1588 Suspend: 1 Teb: 7efd8000 Unfrozen Chrome_ChildIOThread . 20 Id: d98.1440 Suspend: 1 Teb: 7efdb000 Unfrozen Main Thread 21 Id: d98.10d4 Suspend: 1 Teb: 7ef4d000 Unfrozen 22 Id: d98.171c Suspend: 1 Teb: 7efd5000 Unfrozen 2:020:x86 ~21 s ntdll32!ZwWaitForMultipleObjects+0x15: 76fa99fd c21400 ret 14h 2:021:x86 kp ChildEBP RetAddr 0399fcd4 7702787d ntdll32!ZwWaitForMultipleObjects+0x15 0399fe68 750feccb ntdll32!TppWaiterpThread+0x328 0399fe74 76fdd24d kernel32!BaseThreadInitThunk+0xe 0399feb4 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0399fecc ntdll32!_RtlUserThreadStart+0x1b 2:021:x86 ~22 s ntdll32!NtWaitForWorkViaWorkerFactory+0x12: 76fab5ee c20800 ret 8 2:022:x86 kp ChildEBP RetAddr 0357f6ec 76f9b927 ntdll32!NtWaitForWorkViaWorkerFactory+0x12 0357f81c 750feccb ntdll32!TppWorkerThread+0x1f6 0357f828 76fdd24d kernel32!BaseThreadInitThunk+0xe 0357f868 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0357f880 ntdll32!_RtlUserThreadStart+0x1b What are these threads and why are they nameless? Did we create these threads at all? (They could have been created by plugins/detours/etc. that we have no control over.) It would be nice if we could name all threads, so you know what you're looking at. Thanks! BJ Berend-Jan SkyLined Wever skyli...@google.com -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev
Re: [chromium-dev] Thread naming
On Thu, Dec 31, 2009 at 1:11 AM, Berend-Jan Wever skyli...@chromium.org wrote: It would be nice if we could name all threads, so you know what you're looking at. It would be nice if threads were required to be given a name as part of creation, perhaps with a central registry to make sure things are unique. If this amount of overhead is enough to prevent you from spinning up a new thread sometimes ... I guess that's a benefit. If it's not important enough to register, maybe it's not important enough to be a thread, and bad thread usage causes a lot of our bugs. -scott (from chromium.org this time) -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev
Re: [chromium-dev] Thread naming
I'm pretty sure we name all the threads we can (or at least used to), I *think* the problem is worker threads in a thread pool, which are started up and shut down automatically, and aren't named (and don't have message loops). When I was doing the work to generate the internal page about:tasks, it was critical to have names on all the threads (that I could), as the data also shows what threads sent and received tasks. Jim On Thu, Dec 31, 2009 at 1:11 AM, Berend-Jan Wever skyli...@chromium.orgwrote: If you do not care about the way threads are run inside a process in Chromium, you can stop reading now. Some of our threads are named, while others are not. See below cdb.exe output for a renderer process: 2:020:x86 ~ 1 Id: d98.1588 Suspend: 1 Teb: 7efd8000 Unfrozen Chrome_ChildIOThread . 20 Id: d98.1440 Suspend: 1 Teb: 7efdb000 Unfrozen Main Thread 21 Id: d98.10d4 Suspend: 1 Teb: 7ef4d000 Unfrozen 22 Id: d98.171c Suspend: 1 Teb: 7efd5000 Unfrozen 2:020:x86 ~21 s ntdll32!ZwWaitForMultipleObjects+0x15: 76fa99fd c21400 ret 14h 2:021:x86 kp ChildEBP RetAddr 0399fcd4 7702787d ntdll32!ZwWaitForMultipleObjects+0x15 0399fe68 750feccb ntdll32!TppWaiterpThread+0x328 0399fe74 76fdd24d kernel32!BaseThreadInitThunk+0xe 0399feb4 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0399fecc ntdll32!_RtlUserThreadStart+0x1b 2:021:x86 ~22 s ntdll32!NtWaitForWorkViaWorkerFactory+0x12: 76fab5ee c20800 ret 8 2:022:x86 kp ChildEBP RetAddr 0357f6ec 76f9b927 ntdll32!NtWaitForWorkViaWorkerFactory+0x12 0357f81c 750feccb ntdll32!TppWorkerThread+0x1f6 0357f828 76fdd24d kernel32!BaseThreadInitThunk+0xe 0357f868 76fdd45f ntdll32!__RtlUserThreadStart+0x23 0357f880 ntdll32!_RtlUserThreadStart+0x1b What are these threads and why are they nameless? Did we create these threads at all? (They could have been created by plugins/detours/etc. that we have no control over.) It would be nice if we could name all threads, so you know what you're looking at. Thanks! BJ Berend-Jan SkyLined Wever skyli...@google.com -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev
