Re: JDBC patch reduces memory consumption

Denis,

Please provide a patch against current CVS. Some of the code below is
probably no longer needed given other changes that have been made in
current sources.

thanks,
--Barry

Denis Perchine wrote:
> Hello,
>
> This patch reduces JDBC memory usage for setString(),
> setBytes(), executeUpdate()
>
> --
> Denis
>
>
>
>
> ------------------------------------------------------------------------
>
> diff -Nur postgresql-7.2-orig/src/interfaces/jdbc/org/postgresql/jdbc2/PreparedStatement.java postgresql-7.2/src/interfaces/jdbc/org/postgresql/jdbc2/PreparedStatement.java
> --- postgresql-7.2-orig/src/interfaces/jdbc/org/postgresql/jdbc2/PreparedStatement.java Tue Jan 15 01:37:33 2002
> +++ postgresql-7.2/src/interfaces/jdbc/org/postgresql/jdbc2/PreparedStatement.java Wed Oct 16 19:44:35 2002
> @@ -118,20 +118,34 @@
> * This is identical to toString() except it throws an exception if a
> * parameter is unused.
> */
> - private synchronized String compileQuery()
> - throws SQLException
> + private synchronized String compileQuery() throws SQLException
> {
> - sbuf.setLength(0);
> - int i;
> -
> - for (i = 0 ; i < inStrings.length ; ++i)
> - {
> - if (inStrings[i] == null)
> - throw new PSQLException("postgresql.prep.param", new Integer(i + 1));
> - sbuf.append (templateStrings[i]).append (inStrings[i]);
> - }
> - sbuf.append(templateStrings[inStrings.length]);
> - return sbuf.toString();
> + synchronized (sbuf) {
> + try {
> + sbuf.setLength(0);
> + int i;
> +
> + // calculate future buffer size
> + int size = templateStrings[inStrings.length].length();
> + for (i = 0 ; i < inStrings.length ; ++i)
> + if (inStrings[i] == null)
> + throw new PSQLException("postgresql.prep.param", new Integer(i + 1));
> + else
> + size += templateStrings[i].length() + inStrings[i].length();
> + sbuf.ensureCapacity(size);
> +
> + for (i = 0 ; i < inStrings.length ; ++i)
> + {
> + if (inStrings[i] == null)
> + throw new PSQLException("postgresql.prep.param", new Integer(i + 1));
> + sbuf.append (templateStrings[i]).append (inStrings[i]);
> + }
> + sbuf.append(templateStrings[inStrings.length]);
> + return sbuf.toString();
> + } finally {
> + sbuf.setLength(0); // free some memory used by buffer
> + }
> + }
> }
>
> /*
> @@ -276,18 +290,31 @@
> synchronized (sbuf)
> {
> sbuf.setLength(0);
> - int i;
> +
> + int i;
> + char c;
> + if (x.length() > 10000) {
> + // calculate buffer size
> + int size = 2 + x.length();
> + for (i = 0 ; i < x.length() ; ++i) {
> + c = x.charAt(i);
> + if (c == '\\' || c == '\'')
> + size ++;
> + }
> + sbuf.ensureCapacity(size);
> + }
>
> sbuf.append('\'');
> for (i = 0 ; i < x.length() ; ++i)
> {
> - char c = x.charAt(i);
> + c = x.charAt(i);
> if (c == '\\' || c == '\'')
> sbuf.append((char)'\\');
> sbuf.append(c);
> }
> sbuf.append('\'');
> set(parameterIndex, sbuf.toString());
> + sbuf.setLength(0); // free some memory used by buffer
> }
> }
> }
> diff -Nur postgresql-7.2-orig/src/interfaces/jdbc/org/postgresql/util/PGbytea.java postgresql-7.2/src/interfaces/jdbc/org/postgresql/util/PGbytea.java
> --- postgresql-7.2-orig/src/interfaces/jdbc/org/postgresql/util/PGbytea.java Sat Jan 5 16:26:23 2002
> +++ postgresql-7.2/src/interfaces/jdbc/org/postgresql/util/PGbytea.java Wed Oct 16 19:44:55 2002
> @@ -62,10 +62,33 @@
> {
> if (p_buf == null)
> return null;
> - StringBuffer l_strbuf = new StringBuffer();
> +
> + int l_int;
> + StringBuffer l_strbuf;
> +
> + if (p_buf.length > 10000) {
> + // calculate buffer size
> + int size = 0;
> + for (int i = 0; i < p_buf.length; i++) {
> + l_int = (int)p_buf[i];
> + if (l_int < 0)
> + l_int = 256 + l_int;
> +
> + if (l_int < 040 || l_int > 0176)
> + size += 5;
> + else if (p_buf[i] == (byte)'\\')
> + size += 4;
> + else
> + size += 1;
> + }
> + l_strbuf = new StringBuffer(size);
> + }
> + else
> + l_strbuf = new StringBuffer();
> +
> for (int i = 0; i < p_buf.length; i++)
> {
> - int l_int = (int)p_buf[i];
> + l_int = (int)p_buf[i];
> if (l_int < 0)
> {
> l_int = 256 + l_int;
>
>
> ------------------------------------------------------------------------
>
>
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