CASSANDRA-20854: Support low-overhead async profiling #4487
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| # AsyncProfiler Flags | ||
| #-Dcassandra.async_profiler.enabled=true|false | ||
| #-Dcassandra.async_profiler.advanced_mode=true|false | ||
| #-Dcassandra.async_profiler.output_directory=/tmp/cassandra-profiling |
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the parameter is declared but not implemented, a logging directory probably is a better default location ...
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| public interface AsyncProfilerMBean | ||
| { | ||
| void start(String event, String outputFormat, int timeout, String outputPath); |
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timeout - duration probably a better name for the parameter + a time unit as a a suffix would be helpful
outputPath - using a path is too dangerous from security point of view, a path to a data file or another file can be specified to cause a DoS (explicitly or using tricks like ../../.., so it is better to allow only a file name with explictly defined set of symbols to use (allowlist is safer than an denylist)
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I left it at timeout, as it is what the actual async profiler is using.
For the outputPath, that makes sense. Changing.
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Regarding timeout - yes, I mixed it up with -d option and what one is asprof option only.
| } | ||
| catch (Throwable t) | ||
| { | ||
| System.out.println("async-profiler initialization ERROR"); |
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printing to out instead of using logging within Cassandra daemon
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| private static AsyncProfilerService profiler; | ||
| private static String testOutputFile = "/tmp/test-profile.html"; |
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should we use TemporaryFolder?
| @Before | ||
| public void setUp() | ||
| { | ||
| ASYNC_PROFILER_ENABLED.setBoolean(true); |
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should we use org.apache.cassandra.distributed.shared.WithProperties?
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All the tests are needed that flag to be true. I think this setup helps with code duplication?
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| @Test | ||
| public void testUnsafeExecute() { |
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the goal of the test is not clear..
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I was trying to set on stone that the safe profiler will fail with arbitrary commands.
| public class Profile extends AbstractCommand { | ||
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| @Option(names = {"-s", "--start"}, description = "Start profiling") | ||
| public boolean start; |
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should start/stop/raw be a subcommand? Or we need some another way to make the options exclusive, they are not used together based on the execute logic..
3 participants
This is a follow up PR on top of
#4255