nodetool sjk¶
Invokes the Swiss Java Knife diagnostic tool.
Synopsis¶
nodetool [connection_options] sjk <sjk_arguments>
Description¶
nodetool sjk provides access to Swiss Java Knife (SJK) diagnostic commands for JVM troubleshooting. SJK offers various tools for analyzing thread dumps, heap usage, and other JVM internals.
Examples¶
Thread Dump¶
nodetool sjk ttop
Stack Trace Analysis¶
nodetool sjk stcap
Help¶
nodetool sjk --help
Common SJK Commands¶
| Command | Description |
|---|---|
ttop |
Thread CPU usage |
stcap |
Stack trace capture |
stcpy |
Stack trace copy |
hh |
Heap histogram |
gc |
GC statistics |
When to Use¶
CPU Analysis¶
# Find threads using most CPU
nodetool sjk ttop -n 10
Thread Analysis¶
# Capture stack traces
nodetool sjk stcap -o stacks.txt
Related Commands¶
| Command | Relationship |
|---|---|
| tpstats | Thread pool statistics |
| gcstats | GC statistics |