shared memory question

Question

shared memory question

JanuszChmiel opened this issue 4 years ago · 8 comments

I have found out, that startarch script contain special command to emulate sharing memory by creating virtual folder /dev/shm. Does it mean, that in this case, build in C library, which is The part of ArchLinux can fully support shared memory? Or is it still necessary to load .so special library to support this feature?

Answer 1 · 2020-08-21T00:28:56.000Z

Stale issue message

Answer 2 · 2020-08-23T03:25:49.000Z

startarch script contain special command to emulate sharing memory by creating virtual folder /dev/shm

This is created by function _PR00TSTRING_ in variable PROOTSTMNT which in turn creates the folder for /dev/shm when it is NOT readable on smartphone. If it is writable on the smartphone, it will simply bind with the device in the smartphone. I would like to hear your feedback about this newly working yay command.

fully support shared memory?

Possibly, I don't know how setupTermuxArch configures on all the devices, and have not tested all the possible Arch Linux programs. At present everything appear to be automated properly.

necessary to load .so special library to support this

The automation has currently advanced to the point of being able to make yay on smartphone easily with the newly TermuxArch created command makeyay. To answer precisely, no it is not necessary to load .so library as far as I can tell. I would like to know more about the shared object libraries present inside the smartphone:

find -L /system -type f -iname "*.*so" 2>/dev/null|wc -l
1059

Do you have any advice or links to literature regarding how to find out how these shared object files can be analyzed, and what their capabilities are when employed on device?

Answer 3 · 2020-08-23T06:31:45.000Z

I will test latest setuparch scriápt and makeyay command. Thank you very much for yours work on shared memory support. Previously, shmget and similar function really required special .so library to work.

Answer 4 · 2020-08-23T13:57:19.000Z

Previously, shmget and similar function really required special .so library
to work.

Can you enumerate the programs that did not work @JanuszChmiel? A short list, if you could provide one. Thank you for replying quickly.

Answer 5 · 2020-08-23T14:08:08.000Z

The question is simple but The answer on it is not so simple. When user did not used androidshmem.so many apps have worked including whole mate desktop, since Mate programmers have coded their apps to determine, if shared memory have been supported or no. When you have started with termuxarch scripts 3 years ago, when /dev/shm have not been created, Seamonkey E-mail did not work. Thanks to error related to shared memory support. Some developers declares, that if shared memory work as it should, that apps should run faster.

Answer 6 · 2020-08-23T14:17:57.000Z

required special .so library

It is actually unset. Array entry FLHDR1[4]="unset LD_PRELOAD" unsets the special .so library in the user's/bin directory. To find out how many times this project unsets, you can use this grep -w unset *.bash command:

printoutstatements.bash:FLHDR1[4]="unset LD_PRELOAD"                          
setupTermuxArch.bash:unset LD_PRELOAD                                         
setupTermuxArch.bash:           else # unset functions and variables
setupTermuxArch.bash:                   unset -f $(grep \_\( "$WFILE"|cut -d"(" -f 1|sort -u|sed ':a;N;$!ba;s/\n/ /g')
setupTermuxArch.bash:                           unset "$NNSET"

Answer 7 · 2020-08-23T14:20:52.000Z

When you have started with termuxarch scripts 3 years ago

We were using much earlier versions of Android then. Its' SELINUX requirements and Termux was not as robust as it is today.

Answer 8 · 2020-08-23T17:52:06.000Z

Some developers declare that if shared memory works as it should apps should run faster.

Speed can be tested with this stdoutbench.sh script. If you would like to help develop it, stdoutbench.shis at this site.