1 #!/usr/sbin/dtrace -Zs 2 /* 3 * j_flowtime.d - snoop Java execution with method flow and delta times. 4 * Written for the Java hotspot DTrace provider. 5 * 6 * $Id: j_flowtime.d,v 1.1.1.1 2015/09/30 22:01:09 christos Exp $ 7 * 8 * This traces activity from all Java processes on the system with hotspot 9 * provider support (1.6.0) and the flag "+ExtendedDTraceProbes". eg, 10 * java -XX:+ExtendedDTraceProbes classfile 11 * 12 * USAGE: j_flowtime.d # hit Ctrl-C to end 13 * 14 * This watches Java method entries and returns, and indents child 15 * method calls. 16 * 17 * FIELDS: 18 * C CPU-id 19 * PID Process ID 20 * TID Thread ID 21 * TIME(us) Time since boot (us) 22 * DELTA(us) Elapsed time from previous line to this line 23 * CLASS.METHOD Java class and method name 24 * 25 * LEGEND: 26 * -> method entry 27 * <- method return 28 * 29 * WARNING: Watch the first column carefully, it prints the CPU-id. If it 30 * changes, then it is very likely that the output has been shuffled. 31 * Changes in TID will appear to shuffle output, as we change from one thread 32 * depth to the next. See Docs/Notes/ALLjavaflow.txt for additional notes. 33 * 34 * COPYRIGHT: Copyright (c) 2007 Brendan Gregg. 35 * 36 * CDDL HEADER START 37 * 38 * The contents of this file are subject to the terms of the 39 * Common Development and Distribution License, Version 1.0 only 40 * (the "License"). You may not use this file except in compliance 41 * with the License. 42 * 43 * You can obtain a copy of the license at Docs/cddl1.txt 44 * or http://www.opensolaris.org/os/licensing. 45 * See the License for the specific language governing permissions 46 * and limitations under the License. 47 * 48 * CDDL HEADER END 49 * 50 * 09-Sep-2007 Brendan Gregg Created this. 51 */ 52 53 /* increasing bufsize can reduce drops */ 54 #pragma D option bufsize=16m 55 #pragma D option quiet 56 #pragma D option switchrate=10 57 58 self int depth[int]; 59 60 dtrace:::BEGIN 61 { 62 printf("%3s %6s/%-5s %-16s %9s -- %s\n", "C", "PID", "TID", "TIME(us)", 63 "DELTA(us)", "CLASS.METHOD"); 64 } 65 66 hotspot*:::method-entry, 67 hotspot*:::method-return 68 /self->last == 0/ 69 { 70 self->last = timestamp; 71 } 72 73 hotspot*:::method-entry 74 { 75 this->delta = (timestamp - self->last) / 1000; 76 this->class = (char *)copyin(arg1, arg2 + 1); 77 this->class[arg2] = '\0'; 78 this->method = (char *)copyin(arg3, arg4 + 1); 79 this->method[arg4] = '\0'; 80 81 printf("%3d %6d/%-5d %-16d %9d %*s-> %s.%s\n", cpu, pid, tid, 82 timestamp / 1000, this->delta, self->depth[arg0] * 2, "", 83 stringof(this->class), stringof(this->method)); 84 self->depth[arg0]++; 85 self->last = timestamp; 86 } 87 88 hotspot*:::method-return 89 { 90 this->delta = (timestamp - self->last) / 1000; 91 this->class = (char *)copyin(arg1, arg2 + 1); 92 this->class[arg2] = '\0'; 93 this->method = (char *)copyin(arg3, arg4 + 1); 94 this->method[arg4] = '\0'; 95 96 self->depth[arg0] -= self->depth[arg0] > 0 ? 1 : 0; 97 printf("%3d %6d/%-5d %-16d %9d %*s<- %s.%s\n", cpu, pid, tid, 98 timestamp / 1000, this->delta, self->depth[arg0] * 2, "", 99 stringof(this->class), stringof(this->method)); 100 self->last = timestamp; 101 } 102