- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Hi,
I'm running vtune on my application in 2 modes: hotspots & locksandwaits. When I run in locksandwaits mode, the application is very slow. Because of that (I think), I don't see any lock contention. I know that when I run without vtune, the app runs much faster, and I have at least one mutex that many threads try to grab.
Any ideas how to make the app run faster under vtune? Am I doing something wrong?
Thanks,
Erez
I'm running vtune on my application in 2 modes: hotspots & locksandwaits. When I run in locksandwaits mode, the application is very slow. Because of that (I think), I don't see any lock contention. I know that when I run without vtune, the app runs much faster, and I have at least one mutex that many threads try to grab.
Any ideas how to make the app run faster under vtune? Am I doing something wrong?
Thanks,
Erez
Link Copied
3 Replies
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Hi Erez,
Locks and Waits analysis will monitor all system APIs (or your own) for synchronization objects or I/O operations, how they impact on performance.
In project properties, you can unselect "Collect Spin time data" item, unselect "Collect signals" item to reduce overheads from the tool. However excluding none interest of modulesis not supported.This means that all modules (used in your program) will be monitored.
Another thing is that you may reduce your test data, sometime it may helps to reduce overheads. For example, using application to test image process size 320x180 is much better than size 1024x768.
Regards, Peter
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Hi Peter,
I'm using the CLI. I couldn't find how can I disable these 2 ("Collect Spin time data" & "Collect signals") from the CLI. Is it supported?
Thanks,
Erez
I'm using the CLI. I couldn't find how can I disable these 2 ("Collect Spin time data" & "Collect signals") from the CLI. Is it supported?
Thanks,
Erez
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Some of these options specific to an analysis type are called 'knobs', and can be listed with '-knob-list '.
For example, 'amplxe-cl -knob-list locksandwaits' will output:
collect-spin-data
Collect synchronization Spin time to identify how long logical CPUs are
executing while their software threads are waiting.
Default value: true
Possible values: true false
collect-signals
Select to view synchronization transitions in the timeline and identify
signalling call stacks for associated waits. The collector instruments
signalling APIs, which causes higher runtime overhead and increases result
size.
Default value: true
Possible values: true false
Use these with the '-knob' option. For example,
amplxe-cl -collect locksandwaits -knob collect-spin-data=false -knob collect-signals=false
Hope this explains it,
Mark
For example, 'amplxe-cl -knob-list locksandwaits' will output:
collect-spin-data
Collect synchronization Spin time to identify how long logical CPUs are
executing while their software threads are waiting.
Default value: true
Possible values: true false
collect-signals
Select to view synchronization transitions in the timeline and identify
signalling call stacks for associated waits. The collector instruments
signalling APIs, which causes higher runtime overhead and increases result
size.
Default value: true
Possible values: true false
Use these with the '-knob' option. For example,
amplxe-cl -collect locksandwaits -knob collect-spin-data=false -knob collect-signals=false
Hope this explains it,
Mark

Reply
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page