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in reply to Re^6: A new CB reader
in thread A new CB reader

Hi Tux,

In truth, I never imagined for pm-cb-g to support both the -m and -M options. The reason I tested pm-cb-g using MCE::Child was for testing the 3 together Tk, MCE::Child, and MCE::Channel on Windows, Linux, and macOS.

Using MCE::Hobo / MCE::Shared. Notice the extra shared-manager process.

$ ps -e | grep perl 68028 ttys001 0:00.32 perl -I../test_mce pm-cb-g -m # main process 68029 ttys001 0:00.01 perl -I../test_mce pm-cb-g -m # shared mgr 68030 ttys001 0:00.01 perl -I../test_mce pm-cb-g -m # control 68031 ttys001 0:00.09 perl -I../test_mce pm-cb-g -m # communicate

Using MCE::Child / MCE::Channel.

$ ps -e | grep perl 68035 ttys001 0:00.29 perl -I../test_mce pm-cb-g -M # main process 68036 ttys001 0:00.01 perl -I../test_mce pm-cb-g -M # control 68037 ttys001 0:00.09 perl -I../test_mce pm-cb-g -M # communicate

Off-topic

Q. Why was MCE::Hobo created?

A. At the time, I wanted a threads-like parallel module to be included with MCE::Shared. It was also helpful for intense testing of MCE::Shared.

Q. Why did I create MCE::Child years later?

A. Well, MCE::Channel is new and included with MCE 1.841. I needed something to complement it including running on Perl 5.8. So, I tried making another threads-like parallel module. MCE::Child uses a common MCE::Channel object for IPC versus IPC handled by the shared-manager process. After several attempts, got it to work including running on the Windows platform.

Q. Which one to choose?

A. MCE::Child is lighter versus MCE::Hobo because not involving the shared-manager process. However, for apps that have shared variables (i.e. shared array, hash, scalar, etc.), then continue using MCE::Hobo. It's a moot point if the shared-manger is already running.

Q. What about MCE::Channel->new versus MCE::Shared->queue?

A. MCE::Channel involves no manager process and behaves very much like a pipe. It eliminates any concerns for Producer(s) running faster than Consumers. For MCE::Shared, items appended to a shared queue are sent to the shared-manager process where the data resides (i.e. in memory). This means the possibility for Producer(s) to run faster than Consumers. But no worries, MCE::Shared::Queue includes the await method for throttling if ever needed.

Regards, Mario