Start/notes.ini Parameters/JavaMaxHeapSize

JavaMaxHeapSize

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Parameter: JavaMaxHeapSize
Short description: Maximum heap size of the Java VM for Java agents and other Domino JVM processes — NOT for HTTP/XPages/Verse (which use HTTPJVMMaxHeapSize). Default 256 MB.

Profile

Parameter
JavaMaxHeapSize
Category
Client configuration
Component
Server, Client
Available since
9.0
Supported versions
9.0.1, 10.0, 11.0, 12.0, 14.0, 14.5, 14.5.1
GUI equivalent
Server document
Possible values
Memory value including suffix, e.g. 256M, 1024M, 2G

Description

Java agents (AMgr) and other Domino server processes that load a JVM use the heap limited by JavaMaxHeapSize. Important: the HTTP task (XPages, Verse, REST) uses a separate parameter HTTPJVMMaxHeapSize — per HCL KB0029777, JavaMaxHeapSize explicitly does NOT apply to HTTP. The default is 256M; for large Java agents, 512M to 2G is common practice.

Example configuration

JavaMaxHeapSize=1024M

Notes & pitfalls

  • On 64-bit platforms, set the value to ≥ 512M when larger Java agents are used. (XPages heap is set separately via HTTPJVMMaxHeapSize.)
  • Requires a restart of the consuming tasks (HTTP, AMgr) or a server restart.
  • Before changing the value due to memory shortages, measure the actual load using Java profiling / heap dumps.
  • The same parameter also takes effect in the Notes Client (e.g. for local Java agents).