-
Notifications
You must be signed in to change notification settings - Fork 721
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #8405 from pshipton/stringbuffergrowth
Grow StringBuffer and StringBuilder aggressively from 1G to 2G
- Loading branch information
Showing
5 changed files
with
94 additions
and
4 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
66 changes: 66 additions & 0 deletions
66
test/functional/cmdLineTests/cmdLineTest_J9tests/src/TestStringBufferAndBuilderGrowth.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,66 @@ | ||
| /******************************************************************************* | ||
| * Copyright (c) 2020, 2020 IBM Corp. and others | ||
| * | ||
| * This program and the accompanying materials are made available under | ||
| * the terms of the Eclipse Public License 2.0 which accompanies this | ||
| * distribution and is available at https://www.eclipse.org/legal/epl-2.0/ | ||
| * or the Apache License, Version 2.0 which accompanies this distribution and | ||
| * is available at https://www.apache.org/licenses/LICENSE-2.0. | ||
| * | ||
| * This Source Code may also be made available under the following | ||
| * Secondary Licenses when the conditions for such availability set | ||
| * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU | ||
| * General Public License, version 2 with the GNU Classpath | ||
| * Exception [1] and GNU General Public License, version 2 with the | ||
| * OpenJDK Assembly Exception [2]. | ||
| * | ||
| * [1] https://www.gnu.org/software/classpath/license.html | ||
| * [2] http://openjdk.java.net/legal/assembly-exception.html | ||
| * | ||
| * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception | ||
| *******************************************************************************/ | ||
|
|
||
| /** | ||
| * @file TestStringBufferAndBuilderGrowth.java | ||
| * @brief Grows a StringBuffer and StringBuilder to Integer.MAX_VALUE | ||
| */ | ||
| public class TestStringBufferAndBuilderGrowth { | ||
|
|
||
| public static void main(String[] args) { | ||
| char[] cbuf = new char[Integer.MAX_VALUE / 32]; | ||
|
|
||
| // Create a StringBuffer big enough that the default algorithm to | ||
| // grow it will overflow Integer.MAX_VALUE. Some smaller sizes could | ||
| // be used without affecting the test, such as the default size, but | ||
| // starting it big avoids unnecessary copying so the test runs faster. | ||
| StringBuffer sbuf = new StringBuffer((Integer.MAX_VALUE / 2) + 1); | ||
| // 17 iterations adds approximately 1G + 64M (minus a few bytes) | ||
| // to the Buffer, causing it to grow. | ||
| for (int i = 0; i < 17; i++) { | ||
| try { | ||
| sbuf.append(cbuf); | ||
| } catch (OutOfMemoryError e) { | ||
| System.out.println("OOM StringBuffer occurred iteration " + i); | ||
| return; | ||
| } | ||
| } | ||
| int sbufCapacity = sbuf.capacity(); | ||
| // sbuf is no longer used after this point and will be GCed. Nulling it | ||
| // isn't technically required for OpenJ9, but make it explicit for clarity. | ||
| sbuf = null; | ||
|
|
||
| // Duplicate the above test for StringBuilder. | ||
| StringBuilder sbld = new StringBuilder((Integer.MAX_VALUE / 2) + 1); | ||
| for (int i = 0; i < 17; i++) { | ||
| try { | ||
| sbld.append(cbuf); | ||
| } catch (OutOfMemoryError e) { | ||
| System.out.println("OOM StringBuilder occurred iteration " + i); | ||
| return; | ||
| } | ||
| } | ||
| int sbldCapacity = sbld.capacity(); | ||
|
|
||
| System.out.println("StringBuffer capacity=" + sbufCapacity + " StringBuilder capacity=" + sbldCapacity); | ||
| } | ||
| } |