Retrieving slow log is a common operation to monitor and debug performance issues in Redis. It can be used to identify slow queries, assess their execution time, and gather other useful information for debugging.
In Python, using the redis-py
library, we can fetch slow logs with the command slowlog_get
.
Example 1: Retrieve all entries from the slow log:
import redis
r = redis.Redis()
# Get the entire slow log
data = r.slowlog_get()
for i in data:
print(i)
In this code, slowlog_get()
without any arguments retrieves all slow log entries. Each entry is a dictionary containing the fields: 'command', 'duration', 'id' and 'time'.
Example 2: Retrieve the last N entries from the slow log:
import redis
r = redis.Redis()
# Get the last 5 slow log entries
data = r.slowlog_get(5)
for i in data:
print(i)
In this example, slowlog_get(5)
retrieves the last 5 entries from the slow log.
slowlog_get(N)
to limit the number of returned entries.Frequently checking slow logs can consume a considerable amount of resources, so it's important not to check too frequently in a high load environment.
slowlog-log-slower-than
and slowlog-max-len
configuration directives.Dragonfly is fully compatible with the Redis ecosystem and requires no code changes to implement.