Forwarding to correct core-libs-dev list. -Chris.
On 31 Jan 2014, at 14:22, Chris Hegarty <chris.hega...@oracle.com> wrote: > Hi Robert, > > I think your patch can be split into two logical, independent, parts. The > first is the use of unsafe to access the String UTF length. The seconds is to > reuse, where possible, the existing StringBuilder instances, skipping of > primitive/object reading/writing where applicable, and general cleanup. > > Since this is a very sensitive area I would like to consider these > separately. To that end, I have taken the changes that are applicable to the > latter, removed any subjective stylistic changes, and made some additional > cleanup improvements. > > http://cr.openjdk.java.net/~chegar/serial_stupp.00/webrev/ > > Specifically, > * I think for clarify and readability SerialCallbackContext > checkAndSetUsed() should be invoked directly. It makes it very > clear what the intent is. > * Skip primitive/object reading/writing if no primitives/objects in > the stream/class. ( I personally don't see any benefit of rounding > up the size of the array, it just seems to add unnecessary > complexity ) > * Move primitive types into getPrimitiveSignature for better reuse > of code. This retains your change to not create the additional > StringBuilder when it is not necessary. > > I am currently running tests on this change. > > -Chris. > > On 07/01/14 13:03, Robert Stupp wrote: >> Hi, >> I've attached the diff to the original email - it has been stripped. >> Here's a second try (inline). >> I've already signed the OCA and it has been approved :) >> Robert >> # HG changeset patch >> # User snazy >> # Date 1387101091 -3600 >> # Sun Dec 15 10:51:31 2013 +0100 >> # Node ID 6d46d99212453017c88417678d08dc8f10da9606 >> # Parent 9e1be800420265e5dcf264a7ed4abb6f230dd19d >> Removed some unnecessary variable assignments. >> ObjectInputStream: >> - skip primitive/object reading if no primitive/objects in class >> - use shared StringBuilder for string reading (prevent superfluous >> object allocations) >> ObjectOutputStream: >> - skip primitive/object writing if no primitive/objects in class >> - use unsafe access to calculate UTF-length >> - use unsafe access in readBytes() and writeChars() methods to access >> String value field >> - removed cbuf field >> ObjectStreamClass/ObjectStreamField: >> - minor improvement in getClassSignature ; share method code with >> ObjectStreamField >> diff --git a/src/share/classes/java/io/ObjectInputStream.java >> b/src/share/classes/java/io/ObjectInputStream.java >> --- a/src/share/classes/java/io/ObjectInputStream.java >> +++ b/src/share/classes/java/io/ObjectInputStream.java >> @@ -39,8 +39,8 @@ >> import java.util.HashMap; >> import java.util.concurrent.ConcurrentHashMap; >> import java.util.concurrent.ConcurrentMap; >> -import java.util.concurrent.atomic.AtomicBoolean; >> import static java.io.ObjectStreamClass.processQueue; >> + >> import sun.reflect.misc.ReflectUtil; >> >> /** >> @@ -534,7 +534,7 @@ >> if (ctx == null) { >> throw new NotActiveException("not in call to readObject"); >> } >> - Object curObj = ctx.getObj(); >> + ctx.getObj(); >> ObjectStreamClass curDesc = ctx.getDesc(); >> bin.setBlockDataMode(false); >> GetFieldImpl getField = new GetFieldImpl(curDesc); >> @@ -1597,7 +1597,7 @@ >> int descHandle = handles.assign(unshared ? unsharedMarker : desc); >> passHandle = NULL_HANDLE; >> >> - ObjectStreamClass readDesc = null; >> + ObjectStreamClass readDesc; >> try { >> readDesc = readClassDescriptor(); >> } catch (ClassNotFoundException ex) { >> @@ -1976,29 +1976,34 @@ >> } >> >> int primDataSize = desc.getPrimDataSize(); >> - if (primVals == null || primVals.length < primDataSize) { >> - primVals = new byte[primDataSize]; >> - } >> - bin.readFully(primVals, 0, primDataSize, false); >> - if (obj != null) { >> - desc.setPrimFieldValues(obj, primVals); >> - } >> - >> - int objHandle = passHandle; >> - ObjectStreamField[] fields = desc.getFields(false); >> - Object[] objVals = new Object[desc.getNumObjFields()]; >> - int numPrimFields = fields.length - objVals.length; >> - for (int i = 0; i < objVals.length; i++) { >> - ObjectStreamField f = fields[numPrimFields + i]; >> - objVals[i] = readObject0(f.isUnshared()); >> - if (f.getField() != null) { >> - handles.markDependency(objHandle, passHandle); >> + if (primDataSize > 0) { >> + if (primVals == null || primVals.length < primDataSize) { >> + primVals = new byte[ ((primDataSize>>4)+1)<<4 ]; >> + } >> + bin.readFully(primVals, 0, primDataSize, false); >> + if (obj != null) { >> + desc.setPrimFieldValues(obj, primVals); >> } >> } >> - if (obj != null) { >> - desc.setObjFieldValues(obj, objVals); >> + >> + int numObjFields = desc.getNumObjFields(); >> + if (numObjFields > 0) { >> + int objHandle = passHandle; >> + ObjectStreamField[] fields = desc.getFields(false); >> + Object[] objVals = new Object[numObjFields]; >> + int numPrimFields = fields.length - objVals.length; >> + for (int i = 0; i < objVals.length; i++) { >> + ObjectStreamField f = fields[numPrimFields + i]; >> + objVals[i] = readObject0(f.isUnshared()); >> + if (f.getField() != null) { >> + handles.markDependency(objHandle, passHandle); >> + } >> + } >> + if (obj != null) { >> + desc.setObjFieldValues(obj, objVals); >> + } >> + passHandle = objHandle; >> } >> - passHandle = objHandle; >> } >> >> /** >> @@ -2377,8 +2382,10 @@ >> private final byte[] buf = new byte[MAX_BLOCK_SIZE]; >> /** buffer for reading block data headers */ >> private final byte[] hbuf = new byte[MAX_HEADER_SIZE]; >> - /** char buffer for fast string reads */ >> + /** char buffer for fast string reads - used by {@link >> #readUTFSpan(long)} */ >> private final char[] cbuf = new char[CHAR_BUF_SIZE]; >> + /** shared string builder for less object allocations - used by >> {@link #readUTFBody(long)}, {@link #readUTFChar(long)} and {@link >> #readUTFSpan(long)} */ >> + private final StringBuilder sbuf = new >> StringBuilder(CHAR_BUF_SIZE); >> >> /** block data mode */ >> private boolean blkmode = false; >> @@ -3044,19 +3051,19 @@ >> * utflen bytes. >> */ >> private String readUTFBody(long utflen) throws IOException { >> - StringBuilder sbuf = new StringBuilder(); >> if (!blkmode) { >> end = pos = 0; >> } >> >> + sbuf.setLength(0); >> while (utflen > 0) { >> int avail = end - pos; >> if (avail >= 3 || (long) avail == utflen) { >> - utflen -= readUTFSpan(sbuf, utflen); >> + utflen -= readUTFSpan(utflen); >> } else { >> if (blkmode) { >> // near block boundary, read one byte at a time >> - utflen -= readUTFChar(sbuf, utflen); >> + utflen -= readUTFChar(utflen); >> } else { >> // shift and refill buffer manually >> if (avail > 0) { >> @@ -3076,10 +3083,10 @@ >> * Reads span of UTF-encoded characters out of internal buffer >> * (starting at offset pos and ending at or before offset end), >> * consuming no more than utflen bytes. Appends read >> characters to >> - * sbuf. Returns the number of bytes consumed. >> + * {@link #sbuf}. Returns the number of bytes consumed. >> */ >> - private long readUTFSpan(StringBuilder sbuf, long utflen) >> - throws IOException >> + private long readUTFSpan(long utflen) >> + throws IOException >> { >> int cpos = 0; >> int start = pos; >> @@ -3111,19 +3118,19 @@ >> throw new UTFDataFormatException(); >> } >> cbuf[cpos++] = (char) (((b1 & 0x1F) << 6) | >> - ((b2 & 0x3F) << 0)); >> + (b2 & 0x3F)); >> break; >> >> case 14: // 3 byte format: 1110xxxx 10xxxxxx >> 10xxxxxx >> b3 = buf[pos + 1]; >> - b2 = buf[pos + 0]; >> + b2 = buf[pos ]; >> pos += 2; >> if ((b2 & 0xC0) != 0x80 || (b3 & 0xC0) != >> 0x80) { >> throw new UTFDataFormatException(); >> } >> cbuf[cpos++] = (char) (((b1 & 0x0F) << 12) | >> - ((b2 & 0x3F) << 6) | >> - ((b3 & 0x3F) << 0)); >> + ((b2 & 0x3F) << 6) | >> + (b3 & 0x3F)); >> break; >> >> default: // 10xx xxxx, 1111 xxxx >> @@ -3150,12 +3157,12 @@ >> >> /** >> * Reads in single UTF-encoded character one byte at a time, >> appends >> - * the character to sbuf, and returns the number of bytes consumed. >> + * the character to {@link #sbuf}, and returns the number of >> bytes consumed. >> * This method is used when reading in UTF strings written in >> block >> * data mode to handle UTF-encoded characters which (potentially) >> * straddle block-data boundaries. >> */ >> - private int readUTFChar(StringBuilder sbuf, long utflen) >> + private int readUTFChar(long utflen) >> throws IOException >> { >> int b1, b2, b3; >> @@ -3181,8 +3188,7 @@ >> if ((b2 & 0xC0) != 0x80) { >> throw new UTFDataFormatException(); >> } >> - sbuf.append((char) (((b1 & 0x1F) << 6) | >> - ((b2 & 0x3F) << 0))); >> + sbuf.append((char) (((b1 & 0x1F) << 6) | (b2 & 0x3F))); >> return 2; >> >> case 14: // 3 byte format: 1110xxxx 10xxxxxx 10xxxxxx >> @@ -3198,8 +3204,8 @@ >> throw new UTFDataFormatException(); >> } >> sbuf.append((char) (((b1 & 0x0F) << 12) | >> - ((b2 & 0x3F) << 6) | >> - ((b3 & 0x3F) << 0))); >> + ((b2 & 0x3F) << 6) | >> + (b3 & 0x3F))); >> return 3; >> >> default: // 10xx xxxx, 1111 xxxx >> diff --git a/src/share/classes/java/io/ObjectOutputStream.java >> b/src/share/classes/java/io/ObjectOutputStream.java >> --- a/src/share/classes/java/io/ObjectOutputStream.java >> +++ b/src/share/classes/java/io/ObjectOutputStream.java >> @@ -35,7 +35,8 @@ >> import java.util.concurrent.ConcurrentHashMap; >> import java.util.concurrent.ConcurrentMap; >> import static java.io.ObjectStreamClass.processQueue; >> -import java.io.SerialCallbackContext; >> + >> +import sun.misc.Unsafe; >> import sun.reflect.misc.ReflectUtil; >> >> /** >> @@ -458,7 +459,7 @@ >> if (ctx == null) { >> throw new NotActiveException("not in call to >> writeObject"); >> } >> - Object curObj = ctx.getObj(); >> + ctx.getObj(); >> ObjectStreamClass curDesc = ctx.getDesc(); >> curPut = new PutFieldImpl(curDesc); >> } >> @@ -1300,7 +1301,7 @@ >> */ >> private void writeString(String str, boolean unshared) throws >> IOException { >> handles.assign(unshared ? null : str); >> - long utflen = bout.getUTFLength(str); >> + long utflen = BlockDataOutputStream.getUTFLength(str); >> if (utflen <= 0xFFFF) { >> bout.writeByte(TC_STRING); >> bout.writeUTF(str, utflen); >> @@ -1527,29 +1528,34 @@ >> desc.checkDefaultSerialize(); >> >> int primDataSize = desc.getPrimDataSize(); >> - if (primVals == null || primVals.length < primDataSize) { >> - primVals = new byte[primDataSize]; >> + if (primDataSize > 0) { >> + if (primVals == null || primVals.length < primDataSize) { >> + primVals = new byte[ ((primDataSize>>4)+1)<<4 ]; >> + } >> + desc.getPrimFieldValues(obj, primVals); >> + bout.write(primVals, 0, primDataSize, false); >> } >> - desc.getPrimFieldValues(obj, primVals); >> - bout.write(primVals, 0, primDataSize, false); >> >> - ObjectStreamField[] fields = desc.getFields(false); >> - Object[] objVals = new Object[desc.getNumObjFields()]; >> - int numPrimFields = fields.length - objVals.length; >> - desc.getObjFieldValues(obj, objVals); >> - for (int i = 0; i < objVals.length; i++) { >> - if (extendedDebugInfo) { >> - debugInfoStack.push( >> - "field (class \"" + desc.getName() + "\", name: \"" + >> - fields[numPrimFields + i].getName() + "\", type: \"" + >> - fields[numPrimFields + i].getType() + "\")"); >> - } >> - try { >> - writeObject0(objVals[i], >> - fields[numPrimFields + i].isUnshared()); >> - } finally { >> + int numObjFields = desc.getNumObjFields(); >> + if (numObjFields > 0) { >> + ObjectStreamField[] fields = desc.getFields(false); >> + Object[] objVals = new Object[numObjFields]; >> + int numPrimFields = fields.length - objVals.length; >> + desc.getObjFieldValues(obj, objVals); >> + for (int i = 0; i < objVals.length; i++) { >> if (extendedDebugInfo) { >> - debugInfoStack.pop(); >> + debugInfoStack.push( >> + "field (class \"" + desc.getName() + "\", name: >> \"" + >> + fields[numPrimFields + i].getName() + "\", >> type: \"" + >> + fields[numPrimFields + i].getType() + "\")"); >> + } >> + try { >> + writeObject0(objVals[i], >> + fields[numPrimFields + i].isUnshared()); >> + } finally { >> + if (extendedDebugInfo) { >> + debugInfoStack.pop(); >> + } >> } >> } >> } >> @@ -1743,15 +1749,11 @@ >> private static final int MAX_BLOCK_SIZE = 1024; >> /** maximum data block header length */ >> private static final int MAX_HEADER_SIZE = 5; >> - /** (tunable) length of char buffer (for writing strings) */ >> - private static final int CHAR_BUF_SIZE = 256; >> >> /** buffer for writing general/block data */ >> private final byte[] buf = new byte[MAX_BLOCK_SIZE]; >> /** buffer for writing block data headers */ >> private final byte[] hbuf = new byte[MAX_HEADER_SIZE]; >> - /** char buffer for fast string writes */ >> - private final char[] cbuf = new char[CHAR_BUF_SIZE]; >> >> /** block data mode */ >> private boolean blkmode = false; >> @@ -1763,6 +1765,18 @@ >> /** loopback stream (for data writes that span data blocks) */ >> private final DataOutputStream dout; >> >> + /** use unsafe to directly access value field in >> java.lang.String */ >> + private static final Unsafe unsafe = Unsafe.getUnsafe(); >> + /** use field offset to directly access value field in >> java.lang.String */ >> + private static final long stringValueOffset; >> + static { >> + try { >> + stringValueOffset = >> unsafe.objectFieldOffset(String.class.getDeclaredField("value")); >> + } catch (NoSuchFieldException e) { >> + throw new InternalError(e); >> + } >> + } >> + >> /** >> * Creates new BlockDataOutputStream on top of given >> underlying stream. >> * Block data mode is turned off by default. >> @@ -1972,35 +1986,23 @@ >> } >> >> public void writeBytes(String s) throws IOException { >> - int endoff = s.length(); >> - int cpos = 0; >> - int csize = 0; >> + char[] sChars = (char[])unsafe.getObject(s, stringValueOffset); >> + int endoff = sChars.length; >> for (int off = 0; off < endoff; ) { >> - if (cpos >= csize) { >> - cpos = 0; >> - csize = Math.min(endoff - off, CHAR_BUF_SIZE); >> - s.getChars(off, off + csize, cbuf, 0); >> - } >> if (pos >= MAX_BLOCK_SIZE) { >> drain(); >> } >> - int n = Math.min(csize - cpos, MAX_BLOCK_SIZE - pos); >> + int n = Math.min(endoff - off, MAX_BLOCK_SIZE - pos); >> int stop = pos + n; >> while (pos < stop) { >> - buf[pos++] = (byte) cbuf[cpos++]; >> + buf[pos++] = (byte) sChars[off++]; >> } >> - off += n; >> } >> } >> >> public void writeChars(String s) throws IOException { >> - int endoff = s.length(); >> - for (int off = 0; off < endoff; ) { >> - int csize = Math.min(endoff - off, CHAR_BUF_SIZE); >> - s.getChars(off, off + csize, cbuf, 0); >> - writeChars(cbuf, 0, csize); >> - off += csize; >> - } >> + char[] sChars = (char[])unsafe.getObject(s, stringValueOffset); >> + writeChars(sChars, 0, sChars.length); >> } >> >> public void writeUTF(String s) throws IOException { >> @@ -2130,25 +2132,21 @@ >> } >> >> /** >> - * Returns the length in bytes of the UTF encoding of the given >> string. >> + * Returns the length in bytes of the UTF encoding of this >> given string. >> */ >> - long getUTFLength(String s) { >> - int len = s.length(); >> + static long getUTFLength(String s) { >> + char[] value = (char[])unsafe.getObject(s, stringValueOffset); >> + int len = value.length; >> long utflen = 0; >> for (int off = 0; off < len; ) { >> - int csize = Math.min(len - off, CHAR_BUF_SIZE); >> - s.getChars(off, off + csize, cbuf, 0); >> - for (int cpos = 0; cpos < csize; cpos++) { >> - char c = cbuf[cpos]; >> - if (c >= 0x0001 && c <= 0x007F) { >> - utflen++; >> - } else if (c > 0x07FF) { >> - utflen += 3; >> - } else { >> - utflen += 2; >> - } >> + char c = value[off++]; >> + if (c >= 0x0001 && c <= 0x007F) { >> + utflen++; >> + } else if (c > 0x07FF) { >> + utflen += 3; >> + } else { >> + utflen += 2; >> } >> - off += csize; >> } >> return utflen; >> } >> @@ -2198,40 +2196,36 @@ >> * 8-byte length header) of the UTF encoding for the given string. >> */ >> private void writeUTFBody(String s) throws IOException { >> + char[] sChars = (char[])unsafe.getObject(s, stringValueOffset); >> + int len = sChars.length; >> int limit = MAX_BLOCK_SIZE - 3; >> - int len = s.length(); >> for (int off = 0; off < len; ) { >> - int csize = Math.min(len - off, CHAR_BUF_SIZE); >> - s.getChars(off, off + csize, cbuf, 0); >> - for (int cpos = 0; cpos < csize; cpos++) { >> - char c = cbuf[cpos]; >> - if (pos <= limit) { >> - if (c <= 0x007F && c != 0) { >> - buf[pos++] = (byte) c; >> - } else if (c > 0x07FF) { >> - buf[pos + 2] = (byte) (0x80 | ((c >> 0) & >> 0x3F)); >> - buf[pos + 1] = (byte) (0x80 | ((c >> 6) & >> 0x3F)); >> - buf[pos + 0] = (byte) (0xE0 | ((c >> 12) & >> 0x0F)); >> - pos += 3; >> - } else { >> - buf[pos + 1] = (byte) (0x80 | ((c >> 0) & >> 0x3F)); >> - buf[pos + 0] = (byte) (0xC0 | ((c >> 6) & >> 0x1F)); >> - pos += 2; >> - } >> - } else { // write one byte at a time to >> normalize block >> - if (c <= 0x007F && c != 0) { >> - write(c); >> - } else if (c > 0x07FF) { >> - write(0xE0 | ((c >> 12) & 0x0F)); >> - write(0x80 | ((c >> 6) & 0x3F)); >> - write(0x80 | ((c >> 0) & 0x3F)); >> - } else { >> - write(0xC0 | ((c >> 6) & 0x1F)); >> - write(0x80 | ((c >> 0) & 0x3F)); >> - } >> + char c = sChars[off++]; >> + if (pos <= limit) { >> + if (c <= 0x007F && c != 0) { >> + buf[pos++] = (byte) c; >> + } else if (c > 0x07FF) { >> + buf[pos + 2] = (byte) (0x80 | ( c & 0x3F)); >> + buf[pos + 1] = (byte) (0x80 | ((c >> 6) & 0x3F)); >> + buf[pos ] = (byte) (0xE0 | ((c >> 12) & 0x0F)); >> + pos += 3; >> + } else { >> + buf[pos + 1] = (byte) (0x80 | ( c & 0x3F)); >> + buf[pos ] = (byte) (0xC0 | ((c >> 6) & 0x1F)); >> + pos += 2; >> + } >> + } else { // write one byte at a time to normalize block >> + if (c <= 0x007F && c != 0) { >> + write(c); >> + } else if (c > 0x07FF) { >> + write(0xE0 | ((c >> 12) & 0x0F)); >> + write(0x80 | ((c >> 6) & 0x3F)); >> + write(0x80 | ( c & 0x3F)); >> + } else { >> + write(0xC0 | ((c >> 6) & 0x1F)); >> + write(0x80 | ( c & 0x3F)); >> } >> } >> - off += csize; >> } >> } >> } >> @@ -2464,7 +2458,10 @@ >> StringBuilder buffer = new StringBuilder(); >> if (!stack.isEmpty()) { >> for(int i = stack.size(); i > 0; i-- ) { >> - buffer.append(stack.get(i-1) + ((i != 1) ? "\n" : "")); >> + buffer.append(stack.get(i - 1)); >> + if (i!=1) { >> + buffer.append('\n'); >> + } >> } >> } >> return buffer.toString(); >> diff --git a/src/share/classes/java/io/ObjectStreamClass.java >> b/src/share/classes/java/io/ObjectStreamClass.java >> --- a/src/share/classes/java/io/ObjectStreamClass.java >> +++ b/src/share/classes/java/io/ObjectStreamClass.java >> @@ -1474,7 +1474,28 @@ >> /** >> * Returns JVM type signature for given class. >> */ >> - private static String getClassSignature(Class<?> cl) { >> + static String getClassSignature(Class<?> cl) { >> + if (cl.isPrimitive()) >> + if (cl == Integer.TYPE) { >> + return "I"; >> + } else if (cl == Byte.TYPE) { >> + return "B"; >> + } else if (cl == Long.TYPE) { >> + return "J"; >> + } else if (cl == Float.TYPE) { >> + return "F"; >> + } else if (cl == Double.TYPE) { >> + return "D"; >> + } else if (cl == Short.TYPE) { >> + return "S"; >> + } else if (cl == Character.TYPE) { >> + return "C"; >> + } else if (cl == Boolean.TYPE) { >> + return "Z"; >> + } else if (cl == Void.TYPE) { >> + return "V"; >> + } >> + >> StringBuilder sbuf = new StringBuilder(); >> while (cl.isArray()) { >> sbuf.append('['); >> @@ -1503,7 +1524,7 @@ >> throw new InternalError(); >> } >> } else { >> - sbuf.append('L' + cl.getName().replace('.', '/') + ';'); >> + sbuf.append('L').append(cl.getName().replace('.', >> '/')).append(';'); >> } >> return sbuf.toString(); >> } >> diff --git a/src/share/classes/java/io/ObjectStreamField.java >> b/src/share/classes/java/io/ObjectStreamField.java >> --- a/src/share/classes/java/io/ObjectStreamField.java >> +++ b/src/share/classes/java/io/ObjectStreamField.java >> @@ -91,7 +91,7 @@ >> this.name = name; >> this.type = type; >> this.unshared = unshared; >> - signature = getClassSignature(type).intern(); >> + signature = ObjectStreamClass.getClassSignature(type).intern(); >> field = null; >> } >> >> @@ -137,7 +137,7 @@ >> name = field.getName(); >> Class<?> ftype = field.getType(); >> type = (showType || ftype.isPrimitive()) ? ftype : Object.class; >> - signature = getClassSignature(ftype).intern(); >> + signature = ObjectStreamClass.getClassSignature(ftype).intern(); >> } >> >> /** >> @@ -286,41 +286,4 @@ >> String getSignature() { >> return signature; >> } >> - >> - /** >> - * Returns JVM type signature for given class. >> - */ >> - private static String getClassSignature(Class<?> cl) { >> - StringBuilder sbuf = new StringBuilder(); >> - while (cl.isArray()) { >> - sbuf.append('['); >> - cl = cl.getComponentType(); >> - } >> - if (cl.isPrimitive()) { >> - if (cl == Integer.TYPE) { >> - sbuf.append('I'); >> - } else if (cl == Byte.TYPE) { >> - sbuf.append('B'); >> - } else if (cl == Long.TYPE) { >> - sbuf.append('J'); >> - } else if (cl == Float.TYPE) { >> - sbuf.append('F'); >> - } else if (cl == Double.TYPE) { >> - sbuf.append('D'); >> - } else if (cl == Short.TYPE) { >> - sbuf.append('S'); >> - } else if (cl == Character.TYPE) { >> - sbuf.append('C'); >> - } else if (cl == Boolean.TYPE) { >> - sbuf.append('Z'); >> - } else if (cl == Void.TYPE) { >> - sbuf.append('V'); >> - } else { >> - throw new InternalError(); >> - } >> - } else { >> - sbuf.append('L' + cl.getName().replace('.', '/') + ';'); >> - } >> - return sbuf.toString(); >> - } >> } >> *Gesendet:* Dienstag, 07. Januar 2014 um 10:05 Uhr >> *Von:* "Chris Hegarty" <chris.hega...@oracle.com> >> *An:* "Robert Stupp" <sn...@gmx.de> >> *Cc:* "core-libs-dev@openjdk.java.net Libs" <core-libs-dev@openjdk.java.net> >> *Betreff:* Re: ObjectIn/OutputStream improvements >> On 15 Dec 2013, at 10:29, Robert Stupp <sn...@gmx.de> wrote: >> >> > Hi, >> > >> > I digged through the object serialization code and found some lines >> that could be optimized to reduce the number of calls to >> System.arraycopy() and temporary object allocations especially during >> string (de)serialization. >> > In short sentences the changes are: >> > ObjectInputStream: >> > - skip primitive/object reading if no primitive/objects in class >> (defaultReadFields method) >> > - use shared StringBuilder for string reading (prevent superfluous >> object allocations of one StingBuilder and one implicit char[] for each >> string being deserialized) >> > ObjectOutputStream: >> > - skip primitive/object writing if no primitive/objects in class >> (defaultWriteFields method) >> > - use unsafe access to calculate UTF-length >> > - use unsafe access in readBytes() and writeChars() methods to access >> String value field >> > - removed cbuf field >> > ObjectStreamClass/ObjectStreamField: >> > - minor improvement in getClassSignature ; share method code with >> ObjectStreamField (return constant string for primitives) >> > >> > I have tested the changes in a big Java installation at a customer >> (backported the Java8 ObjectIn/OutputStream including the changes to >> Java6) and a long running real application performance test resulted in >> reduced CPU usage (from about 60% per server to 50%). >> > The changes I made in openjdk8 pass all tests. >> > >> > Since I have no experience how to contribute code to openjdk in form >> of a push/changeset I have added the diff (hg export -g) to this email. >> >> Did you attach the diffs? I don’t see any attachment, it may be that the >> attachment was stripped. Can you try resending inline? >> >> You should take a look at the OpenJDK How to Contribute page [1]. Paying >> particular attention to the OCA, without it we will not be able to move >> your patch forward. >> >> Thanks, >> -Chris. >> >> [1] http://openjdk.java.net/contribute/ >> >> > >> > Robert >> > >> >
