This document describes concerns and limitations to be considered when allocating resources for your a9s Search plans.
a9s Search uses the plugins repository-s3 and repository-azure for backup and restore. Those are the only backend storages supported for a9s Search and currently they do not support SSL with unknown certificate issuers.
OpenSearch runs in a JVM, a9s Search
configures the maximum and minimum heap size (
46% of the total memory.
Keep in mind that memory is used for other essential operations, so it is normal for an
OpenSearch process to report a higher memory usage than this. The remaining available memory is
shared between other internal OpenSearch processes, side processes, and OS.
a9s Search does not limit the size of memory that can be locked, as soon as OpenSearch starts, the heap size is locked from the total memory, making it unavailable for other processes.
OpenSearch uses a lot of files. It can happen that in a given moment, a vast number of files are
opened by the OpenSearch processes. a9s Search configures the service instances with a
maximum number open files of
ulimit -n 65536). Bear this in mind in case your usage of the
cluster favors opening a vast number of files.
If the OpenSearch process runs out of file descriptors, data loss might happen.
Number of Threads
OpenSearch uses a thread pool for multiple operations, a9s Search configures the maximum
number of processes for OpenSearch as 4096 (
ulimit -u 4096).