ZooKeeper top

Author: Patrick Hunt (follow me on twitter)

Summary

This project provides a unix “top” like utility for ZooKeeper.

Example

Running:

./zktop.py --servers "localhost:2181,localhost:2182,localhost:2183"

shows a screen like:

Ensemble -- nodecount:10 zxid:0x1300000001 sessions:4

SERVER           PORT M      OUTST    RECVD     SENT CONNS MINLAT AVGLAT MAXLAT
localhost        2181 F          0       93       92     2      2      7     13
localhost        2182 F          0       37       36     1      0      0      0
localhost        2183 L          0       36       35     1      0      0      0

CLIENT           PORT I   QUEUE RECVD  SENT
127.0.0.1       34705 1       0    56    56
127.0.0.1       35943 1       0     1     0
127.0.0.1       33999 1       0     1     0
127.0.0.1       37988 1       0     1     0

What’s Apache ZooKeeper?

From the official site: “ZooKeeper is a high-performance coordination service for distributed applications.”

It exposes common services – such as naming, configuration management, synchronization, and group services – in a simple interface so you don’t have to write them from scratch. You can use it off-the-shelf to implement consensus, group management, leader election, and presence protocols.

zktop.py

0) Top line is overall cluster status
1-n) Lines 1-n are for the n servers
n+1 and below are for client connections

Usage

Usage: zktop.py [options]

Options:
  -h, --help         show this help message and exit
  --servers=SERVERS  comma separated list of host:port (default
                     localhost:2181)
  -n, --names        resolve session name from ip (default False)
  --fix_330          workaround for a bug in ZK 3.3.0

—fix_330 works around a bug in ZooKeeper 3.3.0, it is only necessary if running the server against that version of ZooKeeper.

The screen refreshes every 3 seconds.

• ‘h’ help
• ‘q’ quits
• ‘r’ resets the server stats
• spacebar updates immediately

License

This project is licensed under the Apache License Version 2.0