Configuration

Table of contents

1. Introduction
2. Command-line options
   1. Bytecode include directory
3. Environment variables
   1. INKO_PRIMARY_THREADS
   2. INKO_SECONDARY_THREADS
   3. INKO_GC_THREADS
   4. INKO_FINALIZER_THREADS
   5. INKO_GENERIC_PARALLEL_THREADS
   6. INKO_REDUCTIONS
   7. INKO_SUSPENSION_CHECK_INTERVAL
   8. INKO_YOUNG_THRESHOLD
   9. INKO_MATURE_THRESHOLD
   10. INKO_HEAP_GROWTH_THRESHOLD
   11. INKO_HEAP_GROWTH_FACTOR
   12. INKO_MAILBOX_THRESHOLD
   13. INKO_MAILBOX_GROWTH_FACTOR
   14. INKO_MAILBOX_GROWTH_THRESHOLD

Introduction

IVM can be configured using two different methods:

1. Command-line options.
2. Environment variables.

In general IVM favours the use of environment variables over command-line options, as environment variables are easier to persist.

Command-line options

Bytecode include directory

The -I / --include option can be specified multiple times, and is used to add a directory to the list of bytecode directories. When IVM loads a bytecode file, it will try to find it in one of these directories.

Environment variables

INKO_PRIMARY_THREADS

An integer specifying the number of threads to use for the primary thread pool.

Defaults to the number of logical CPU cores.

INKO_SECONDARY_THREADS

An integer specifying the number of threads to use for the secondary thread pool.

Defaults to the number of logical CPU cores.

INKO_GC_THREADS

An integer specifying the number of threads to use for the garbage collector.

Defaults to 2.

INKO_FINALIZER_THREADS

An integer specifying the number of threads to use for finalising objects.

Defaults to 2.

INKO_GENERIC_PARALLEL_THREADS

An integer specifying the number of threads to use for various parallel operations, such as scanning the stack of a process to garbage collect.

Defaults to the number of physical CPU cores.

INKO_REDUCTIONS

An integer specifying the number of reductions that take place before a process is suspended.

Defaults to 1000.

INKO_SUSPENSION_CHECK_INTERVAL

An integer specifying the number of milliseconds to wait between checking for suspended processes.

Defaults to 100 (milliseconds).

INKO_YOUNG_THRESHOLD

An integer specifying the amount of memory that can be allocated in the young generation before triggering a young collection.

Defaults to 8 388 608 (8 MB).

INKO_MATURE_THRESHOLD

An integer specifying the amount of memory that can be allocated in the mature generation before triggering a full collection.

Defaults to 16 777 216 (16 MB).

INKO_HEAP_GROWTH_THRESHOLD

A float ranging from 0.0 (0%) to 1.0 (100%), specifying the percentage of memory that should still remain in use after a garbage collection cycle, before increasing the process heap's garbage collection threshold.

Defaults to 0.9.

INKO_HEAP_GROWTH_FACTOR

A float used to grow the process heap's garbage collection threshold if the growth threshold is exceeded. The threshold is increased by multiplying it with this value.

Defaults to 1.5.

INKO_MAILBOX_THRESHOLD

An integer specifying the amount of memory that can be allocated in the mailbox heap before triggering a mailbox garbage collection.

Defaults to 32 768 (32 KB).

INKO_MAILBOX_GROWTH_FACTOR

A float used to grow the mailbox heap's garbage collection threshold if the growth threshold is exceeded. The threshold is increased by multiplying it with this value.

Defaults to 1.5.

INKO_MAILBOX_GROWTH_THRESHOLD

A float ranging from 0.0 (0%) to 1.0 (100%), specifying the percentage of memory that should still remain in use after a garbage collection cycle, before increasing the mailbox heap's garbage collection threshold.

Defaults to 0.9.