• tcak (12/12) Jul 15 2016 It is great to see memory usage on Xcode while running an iOS app.
• Jack Stouffer (2/15) Jul 15 2016 Do you know about --profile=gc?
• tcak (8/28) Jul 15 2016 1. Never worked for me in a multithreaded program.
• Andrei Alexandrescu (5/13) Jul 15 2016 Wouldn't that make things too slow to be practical? The other profilers
• tcak (9/29) Jul 15 2016 Hmm, I will check it out. Haven't tested it for a while.
• Andrei Alexandrescu (3/8) Jul 15 2016 I think the consecrated method is to use in-memory storage and serve it
• Jacob Carlborg (5/6) Jul 15 2016 Have you tried to run a D application inside Xcode to get the same
• tcak (2/7) Jul 15 2016 Never used D on Xcode, nor I knew it was possible.
• Jacob Carlborg (7/8) Jul 16 2016 Well, when it comes to using the debugger in Xcode or profiling using

tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:

It is great to see memory usage on Xcode while running an iOS app.

What I thought is that:

1. GC knows available heap memory locations and their length.
2. GC can detect what parts of heap is in use.
3. A program can create a file to write (stdout, stderr, etc.)


So, when desired (e.g. use of a compiler flag), on runtime, GC 
could write statistical information to a file descriptor every 
time it runs. So, anyone could write a program to read that 
information to turn it into a graphical chart for profiling 
information.

Does GC have any support to collect this type of information 
currently?

Jack Stouffer <jack jackstouffer.com> writes:

On Friday, 15 July 2016 at 16:14:39 UTC, tcak wrote:
 It is great to see memory usage on Xcode while running an iOS 
 app.

 What I thought is that:

 1. GC knows available heap memory locations and their length.
 2. GC can detect what parts of heap is in use.
 3. A program can create a file to write (stdout, stderr, etc.)


 So, when desired (e.g. use of a compiler flag), on runtime, GC 
 could write statistical information to a file descriptor every 
 time it runs. So, anyone could write a program to read that 
 information to turn it into a graphical chart for profiling 
 information.

 Does GC have any support to collect this type of information 
 currently?

Do you know about --profile=gc?

tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:

On Friday, 15 July 2016 at 16:21:15 UTC, Jack Stouffer wrote:
 On Friday, 15 July 2016 at 16:14:39 UTC, tcak wrote:
 It is great to see memory usage on Xcode while running an iOS 
 app.

 What I thought is that:

 1. GC knows available heap memory locations and their length.
 2. GC can detect what parts of heap is in use.
 3. A program can create a file to write (stdout, stderr, etc.)


 So, when desired (e.g. use of a compiler flag), on runtime, GC 
 could write statistical information to a file descriptor every 
 time it runs. So, anyone could write a program to read that 
 information to turn it into a graphical chart for profiling 
 information.

 Does GC have any support to collect this type of information 
 currently?

 Do you know about --profile=gc?

1. Never worked for me in a multithreaded program.
2. I am not able to retrieve that data on runtime by another 
application to see close to real-time statistics.

I know that profiling data is kept in memory, and written to file 
at the end of program. Instead it could write it to a file 
descriptor and not care about whether a program is reading it. 
Let the kernel handle that part.

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 07/15/2016 12:31 PM, tcak wrote:
 Do you know about --profile=gc?

 1. Never worked for me in a multithreaded program.

Could you please give it another look. Walter fixed it relatively recently.

 2. I am not able to retrieve that data on runtime by another application
 to see close to real-time statistics.

 I know that profiling data is kept in memory, and written to file at the
 end of program. Instead it could write it to a file descriptor and not
 care about whether a program is reading it. Let the kernel handle that
 part.

Wouldn't that make things too slow to be practical? The other profilers 
I know of also keep counters in memory.


Andrei

tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:

On Friday, 15 July 2016 at 17:04:35 UTC, Andrei Alexandrescu 
wrote:
 On 07/15/2016 12:31 PM, tcak wrote:
 Do you know about --profile=gc?

 1. Never worked for me in a multithreaded program.

 Could you please give it another look. Walter fixed it 
 relatively recently.

Hmm, I will check it out. Haven't tested it for a while.

 2. I am not able to retrieve that data on runtime by another 
 application
 to see close to real-time statistics.

 I know that profiling data is kept in memory, and written to 
 file at the
 end of program. Instead it could write it to a file descriptor 
 and not
 care about whether a program is reading it. Let the kernel 
 handle that
 part.

 Wouldn't that make things too slow to be practical? The other 
 profilers I know of also keep counters in memory.


 Andrei

If it is about speed, we can still use a public shared memory for 
that purpose. So, statistical messages can be written in shared 
memory, and other program reads from that to get those messages. 
A suitable communication protocol can be implemented in way. At 
the end, our purpose is to provide powerful toys to ease 
development.

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 07/15/2016 03:42 PM, tcak wrote:
 If it is about speed, we can still use a public shared memory for that
 purpose. So, statistical messages can be written in shared memory, and
 other program reads from that to get those messages. A suitable
 communication protocol can be implemented in way. At the end, our
 purpose is to provide powerful toys to ease development.

I think the consecrated method is to use in-memory storage and serve it 
upon request (e.g. by means of an API or interrupt). -- Andrei

Jacob Carlborg <doob me.com> writes:

On 2016-07-15 18:14, tcak wrote:
 It is great to see memory usage on Xcode while running an iOS app.

Have you tried to run a D application inside Xcode to get the same 
information? Or is it not available due to the GC?

-- 
/Jacob Carlborg

tcak <1ltkrs+3wyh1ow7kzn1k sharklasers.com> writes:

On Friday, 15 July 2016 at 19:22:41 UTC, Jacob Carlborg wrote:
 On 2016-07-15 18:14, tcak wrote:
 It is great to see memory usage on Xcode while running an iOS 
 app.

 Have you tried to run a D application inside Xcode to get the 
 same information? Or is it not available due to the GC?

Never used D on Xcode, nor I knew it was possible.

Jacob Carlborg <doob me.com> writes:

On 2016-07-15 21:39, tcak wrote:

 Never used D on Xcode, nor I knew it was possible.

Well, when it comes to using the debugger in Xcode or profiling using 
Instruments both can load any application. Although you won't get any 
demangling in the debugger but if you and the source files to an Xcode 
project you get source code location.

-- 
/Jacob Carlborg