jstat Garbage Collection visualizer
jstat is useful for getting a quick overview of the memory characteristics of a java process. However, the output is tabular and hard to interpret quickly. This javascript application displays jstat output graphically. It can be used as a first step in understanding memory and garbage collection behavior a java application. It is not intended to be exact.
To use this tool, run jstat as follows:
jstat -gc -t PID STEP
PID is the process ID of the java process to monitor
STEP is the sample timestep
Example: jstat -gc -t 5924 1000ms
Example output:
Timestamp S0C S1C S0U S1U EC EU OC OU PC PU YGC YGCT FGC FGCT GCT 365.8 9152.0 9792.0 864.0 0.0 153600.0 139935.9 160128.0 108914.2 132160.0 96205.9 86 1.301 4 2.316 3.617 366.8 9152.0 9792.0 864.0 0.0 153600.0 144438.1 160128.0 108914.2 132160.0 96208.1 86 1.301 4 2.316 3.617 367.8 9152.0 9792.0 864.0 0.0 153600.0 147382.9 160128.0 108914.2 132160.0 96208.5 86 1.301 4 2.316 3.617 368.8 9152.0 9792.0 864.0 0.0 153600.0 150079.9 160128.0 108914.2 132160.0 96210.6 86 1.301 4 2.316 3.617 369.8 11328.0 9792.0 0.0 9787.9 153600.0 4621.7 160128.0 109481.9 132160.0 96211.1 87 1.320 4 2.316 3.636 370.8 11328.0 9792.0 0.0 9787.9 153600.0 4621.7 160128.0 109481.9 132160.0 96211.1 87 1.320 4 2.316 3.636 371.8 11328.0 9792.0 0.0 9787.9 153600.0 4621.7 160128.0 109481.9 132160.0 96211.1 87 1.320 4 2.316 3.636 372.8 11328.0 9792.0 0.0 9787.9 153600.0 4658.1 160128.0 109481.9 132160.0 96211.3 87 1.320 4 2.316 3.636 373.8 11328.0 13376.0 9173.0 0.0 147968.0 0.0 160128.0 109481.9 132160.0 96211.3 88 1.360 5 2.879 4.240 374.8 11328.0 13376.0 0.0 0.0 147968.0 764.7 160128.0 87818.8 137920.0 96207.7 88 1.360 5 2.879 4.240 375.8 11328.0 13376.0 0.0 0.0 147968.0 764.7 160128.0 87818.8 137920.0 96208.9 88 1.360 5 2.879 4.240 376.8 11328.0 13376.0 0.0 0.0 147968.0 764.7 160128.0 87818.8 137920.0 96208.9 88 1.360 5 2.879 4.240 377.8 11328.0 13376.0 0.0 0.0 147968.0 2212.3 160128.0 87818.8 137920.0 96209.5 88 1.360 5 2.879 4.240 378.8 11328.0 13376.0 0.0 0.0 147968.0 2975.2 160128.0 87818.8 137920.0 96209.5 88 1.360 5 2.879 4.240 379.8 11328.0 13376.0 0.0 0.0 147968.0 7376.9 160128.0 87818.8 137920.0 96326.5 88 1.360 5 2.879 4.240 381.1 11328.0 13376.0 0.0 0.0 147968.0 8761.5 160128.0 87818.8 137920.0 96518.0 88 1.360 5 2.879 4.240 382.1 11328.0 13376.0 0.0 0.0 147968.0 8761.5 160128.0 87818.8 137920.0 96594.6 88 1.360 5 2.879 4.240 383.1 11328.0 13376.0 0.0 0.0 147968.0 10610.1 160128.0 87818.8 137920.0 96693.8 88 1.360 5 2.879 4.240 384.1 11328.0 13376.0 0.0 0.0 147968.0 11259.0 160128.0 87818.8 137920.0 96823.8 88 1.360 5 2.879 4.240 385.1 11328.0 13376.0 0.0 0.0 147968.0 11487.1 160128.0 87818.8 137920.0 96913.2 88 1.360 5 2.879 4.240
Copy and paste the output into the text area below, then click 'Plot'
A note about the key: The horizontal axis of each chart is the time since the JVM started. Light-blue vertical bars indicate a young garbage collection event, Yellow vertical bars indicate a full garbage collection event. Due to resolution limitations for large data sets these may not always be rendered.
