Using a lot of RAM

[drthinh]

I used miniJVM to demostrate a tiny console app 'Hello World' without any GUI library, it spent 35MB RAM only with minimal runtime? Are there any problem with memory model?

[digitalgust]

Change jvm.h
#define _JVM_DEBUG_LOG_LEVEL 01
change 01 to 02 ,You will get the gc detail information.

Running SpecTest:
mini_jvm.exe -bootclasspath ../lib/minijvm_rt.jar -cp ../libex/minijvm_test.jar test/SpecTest

Output:

[INFO]main thread start
[JDWP]waiting for jdwp(port:8000) debug client connected...
test start
[INFO]thread start 10c75aa00
[INFO]gc obj: 4200->648   heap : 346732 -> 54060  stop_world: 0  gc:0
[INFO]gc obj: 648->648   heap : 54060 -> 54060  stop_world: 1  gc:0
[INFO]gc obj: 648->648   heap : 54060 -> 54060  stop_world: 0  gc:0
[INFO]gc obj: 648->648   heap : 54060 -> 54060  stop_world: 0  gc:0
[INFO]thread over 10c75aa00 , spent : 4010
test end
[INFO]main thread over 10c235e90 , spent : 4027
[INFO]garbage clear start
[INFO]objs size :648
[INFO]gc obj: 2146->882   heap : 186151 -> 83168  stop_world: 1  gc:0
[INFO]gc obj: 882->882   heap : 83168 -> 83168  stop_world: 0  gc:0
[INFO]gc obj: 882->64   heap : 83168 -> 20824  stop_world: 0  gc:0
[INFO]gc obj: 64->64   heap : 20824 -> 20824  stop_world: 0  gc:0
[INFO]gc obj: 64->0   heap : 20824 -> 0  stop_world: 0  gc:0
[INFO]gc obj: 0->0   heap : 0 -> 0  stop_world: 0  gc:0
[INFO]objs size :0
[INFO]jvm destoried heap size = 0

Process finished with exit code 0

[digitalgust]

miniJVM is using ltalloc to allocate memory, system allocated memory is more than jvm usage, comment the line in d_type.h to disable ltalloc, will get the more accurate memory.
//#define MEM_ALLOC_LTALLOC

[drthinh]

Thank you very much, after disable ltalloc, it spends only 12MB RAM, I feel much better. I don't know why ltalloc was used and what will happend when turn it off. Because of lacking document, I don't know how to program with the runtime, especially java.net library, it doesn't have API to connect internet neither https protocol. I hope you would add more features and documents for this project, I really love it, thank you

[digitalgust]

ltalloc is a little faster than c malloc on iOS/macOS/win, but equals to Linux/Android, but it waste memory than c malloc. Https on the way, I am construct it . There are few documents now , plan to write it.
now please clone the example project :
https://github.com/digitalgust/BiBiX

[drthinh]

I have update the library again, it runs well :) but I have a problem with start GUI app when window fullscreen, I can't click the buttons again, may be because of the change of coordinate . Btw, could you update Android binary version. Thanks!

[digitalgust]

The windows app resize to fullscreen , it works in my win10x64, I don't know what happen in your situation, do you have more information about this.
I updated android app.

[drthinh]

Everything was ok until I sign in BiBiX, after that I resized the window to fullscreen I couldnt click three bottom buttons.
The new apk cant be installed with Android version 10, it was blocked by Google Protect because of unknow programmer ID.

[digitalgust]

android submited a debug version, plz try it .
bibix menu could not click , let me check what happened .

[drthinh]

I tried to install that apk many times, but it still be blocked by Google Protect. I will try to build another ones. Thank you, hope you could find the problem with bibix app 😀

[digitalgust]

menu can't be click bug fixed.

[digitalgust]

android binary , may be you can build it yourself , Android Studio open project
miniJVM/mobile/androidapp
build and run .

[drthinh]

All above issues are solved 😁. Btw, when I compare speed, RAM and CPU usage, the mini_jvm takes 150-200% slower, more resource especially CPU used than JVM in same console tests: calculate primes < 1000, Fibonacci,... Could you have a solution for this issue? Thank you.

[digitalgust]

oracle jvm or openjdk jvm did lots of optimizations for jit , the minijvm implemented jit ,but few of static analysts and optimizations ,so the minijvm have worse performance , minijvm developed for iOS and android mainly, Only provide a same development and running environment for pc, And the iOS platform does not allow applications to run in jit mode. alternately ,there is a java2c ( https://github.com/digitalgust/java2c ) project can convert minijvm jar to c source , the performance is very closely to oracle jvm .

[drthinh]

Your project have some similar plans like corona mobile sdk/solar2D which use Lua to program in Android/iOs/desktop (embedded source code in apk - I don't like that) or Codename One (closed source and limited file compiled), but I think your solution is better because of Java language and native high performance graphic lib for mobile. But I would like to hearing from your desktop solution like native Windows GUI (awt implementation..).
Btw BiBiX (Windows 10x64) cant type Unicode characters.
Thanks.

[digitalgust]

minijvm app can update jar file anytime , then need restart app only.
there are no plan to develop a new GUI for windows, like awt , but there are some of open source project like OpenAWT and more ,to adapt to minijvm is not difficult , minijvm gui lib support Nanovg api etc.
the recent plan to :
implement https
dump vm memory like virtualvm
hard limit vm memory to specified value
fix bugs and optimize gui system.

[drthinh]

Because of the libgui support GUI controls like TextBox, Button, ListBox,...but in desktop I still can't type unicode, or copy from clipboard...so I must find another solution. I will choose one of your suggestions, could you write some tips for using minijvm native interface?.
I hope you soon add https protocol 😀

[digitalgust]

can't type unicode, can't using clipboard, these are issues, i will repair it, can u shows more information about this , because i can type chinese in win platforms, gui support clipboard too

[drthinh]

I'm using Unikey, but instead of display "trần văn dũng" it showed "trn vn dng", unicode characters "ầ ă ũ" weren't appeared.
First startup screen, the textbox "Download app from website" doesnt show context menu Paste at right click nor Ctrl + V
When run BiBiX, have context menu when right click but nothing show in textbox login
I copy Chinese characters to textbox but it still show nothing

[digitalgust]

clipboard bug fixed , I am solving Vietnam language display issue

[drthinh]

clipboard is now ok. But I still can't paste Unicode or type Unicode to textbox. The textbox have Ctrl + V but dont have Ctrl + Z?
btw, it takes more resource than the previous, 99MB RAM when startup.

[digitalgust]

ctrl+z can be add, it 's not the fixed heap using every times, it related with gc period. if the gc work per 30s, it would be more heap use , so i plan to limit the heap to specify value.

[drthinh]

Oh, I'm looking forward to your next mini_jvm version

[digitalgust]

https supported.
I am finding a font to support Vietnam

[drthinh]

I have tried with your previous https.c/https.h - mbedtls wrapper (for Mac but with little changes to compile in Windows), it didn't run, but now, your lastest https library run smooth. I expected it so much.
All popular unicode fonts support Vietnam characters, examples: Times New Roman, Consolas, Courier New, Arial,...

[digitalgust]

update gui jar to support full unicode font glyph.

[drthinh]

Unicode is ok now!
I hope can use mouse to select text (now only can use right mouse -> select text) and Ctrl +Z
BTW, the last BiBiX crashed when enter random login text, can't go back/exit

[digitalgust]

update textfield to support hotkey , how the bib crushed , could you delete app and redownload it try again.

[drthinh]

I deleted app and downloaded the lastest binaries, it's now OK, very smooth, only one downside it took 120MB RAM on startup