#!/usr/sbin/dtrace -Zs /* * Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* */ /* * Usage: * 1. object_allocation_stat.d -c "java ..." TOP_RESULTS_COUNT INTERVAL_SECS * 2. object_allocation_stat.d -p JAVA_PID TOP_RESULTS_COUNT INTERVAL_SECS * * This script collects statistics about TOP_RESULTS_COUNT (default is 25) * object allocations every INTERVAL_SECS (default is 60) seconds. * * The results are displayed in ascending order which means that the highest * allocated type is listed last. The script can be improved to sort the * results in reverse order when DTrace supports it. * * Notes: * - The object-alloc probe is disabled by default since it incurs * performance overhead to the application. To trace object-alloc probe, * you need to turn on the ExtendedDTraceProbes VM option. * You can either start the application with -XX:+ExtendedDTraceProbes * option or use the jinfo command to enable it at runtime as follows: * * jinfo -flag +ExtendedDTraceProbes * */ #pragma D option quiet #pragma D option destructive #pragma D option defaultargs #pragma D option bufsize=16m #pragma D option aggrate=100ms self char *str_ptr; self string class_name; long long ALLOCATED_OBJECTS_CNT; int INTERVAL_SECS; :::BEGIN { SAMPLE_NAME = "hotspot object allocation tracing"; TOP_RESULTS_COUNT = $1 ? $1 : 25; INTERVAL_SECS = $2 ? $2 : 60; ALLOCATED_OBJECTS_CNT = 0; SAMPLING_TIME = timestamp + INTERVAL_SECS * 1000000000ull; LINE_SEP = "------------------------------------------------------------------------"; printf("BEGIN %s\n\n", SAMPLE_NAME); } /* * hotspot:::object-alloc probe arguments: * arg0: uintptr_t, Java thread id * arg1: char*, a pointer to mUTF-8 string containing the name of * the class of the object being allocated * arg2: uintptr_t, the length of the class name (in bytes) * arg3: uintptr_t, the size of the object being allocated */ hotspot$target:::object-alloc { ALLOCATED_OBJECTS_CNT ++; self->str_ptr = (char*) copyin(arg1, arg2+1); self->str_ptr[arg2] = '\0'; self->class_name = (string) self->str_ptr; @allocs_count[self->class_name] = count(); @allocs_size[self->class_name] = sum(arg3); } tick-1sec /timestamp > SAMPLING_TIME/ { printf("\n"); printf("%s\n", LINE_SEP); printf("%Y\n", walltimestamp); printf("%s\n", LINE_SEP); printf("\n"); printf("Top %d allocations by size:\n", TOP_RESULTS_COUNT); trunc(@allocs_size, TOP_RESULTS_COUNT); printa("%10@d %s\n", @allocs_size); printf("\n"); printf("Top %d allocations by count:\n", TOP_RESULTS_COUNT); trunc(@allocs_count, TOP_RESULTS_COUNT); printa("%10@d %s\n", @allocs_count); printf("\nTotal number of allocated objects: %d\n", ALLOCATED_OBJECTS_CNT); SAMPLING_TIME = timestamp + INTERVAL_SECS * 1000000000ull; } :::END { printf("\n"); printf("%s\n", LINE_SEP); printf("%Y\n", walltimestamp); printf("%s\n", LINE_SEP); printf("\n"); printf("Top %d allocations by size:\n", TOP_RESULTS_COUNT); trunc(@allocs_size, TOP_RESULTS_COUNT); printa("%10@d %s\n", @allocs_size); printf("\n"); printf("Top %d allocations by count:\n", TOP_RESULTS_COUNT); trunc(@allocs_count, TOP_RESULTS_COUNT); printa("%10@d %s\n", @allocs_count); printf("\nTotal number of allocated objects: %d\n", ALLOCATED_OBJECTS_CNT); printf("\nEND of %s\n", SAMPLE_NAME); } syscall::rexit:entry, syscall::exit:entry /pid == $target/ { exit(0); }