XTRIM command in Redis is used to trim the number of messages in a stream to a maximum length. Common use cases include:
Here are examples of how to use
XTRIM in Ruby using the
redis-rb client library.
~) indicates that the trimming is not strict. Redis might decide to remove more entries in one go for efficiency.
=) to enforce a stricter limit where Redis will try to trim the stream exactly to the specified length, if possible.
XTRIM, it's often better to use the approximate trimming (with
~) as it can be more efficient and reduce the number of operations needed to trim the stream.
XTRIMmight remove more elements than specified when using approximate trimming.
XTRIMwithout understanding its performance implications, especially on very large streams.
Q: Can I use
XTRIM with consumer groups?
A: Yes, but you must ensure that you do not trim entries that have pending messages for any consumer group.
Q: How does
XTRIM affect memory usage?
A: By trimming streams, you reduce the memory footprint of your Redis instance, as old entries are deleted.