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POHow do i fix: OutOfMemoryError with External Sorting
 

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  1. POHow do i fix: OutOfMemoryError with External Sorting
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    <p>This program basically reads a huge amount of data from a binary file named data.bin where each item in the file is 1024 bytes long. the first 24 bytes of each item is the key and the remaining 1000 bytes just random information. and it adds all these items into an array list called "items" where it can then be sorted using a merge sort algorithm. </p> <p>but im getting an OutOfMemoryError on the line commented with ERROR after adding about 227475 items. This is all supposed to be externally sorted but its obviously not working right. so how could i split up the huge amount of items into smaller sets to be sorted then merged?</p> <pre><code> public static void main(String[] args) { System.out.println("Welcome to external merge sorter."); ArrayList&lt;Entry&lt;BigInteger, BigInteger&gt;&gt; items = new ArrayList&lt;Entry&lt;BigInteger, BigInteger&gt;&gt; (); TEntry&lt;BigInteger, BigInteger&gt; en = null; try { RandomAccessFile data = new RandomAccessFile("data.bin","rws"); System.out.println("Found file data.bin."); long length = data.length(); long recs = length / 1024; long count = 0; byte []b = new byte[1024]; System.out.println("Sorting..."); while(count &lt; recs) { count++; data.readFully(b); byte []key = Arrays.copyOfRange(b, 0, 24); byte []value = Arrays.copyOfRange(b, 24, 1024); System.out.println(count); //ERROR en = new TEntry&lt;BigInteger, BigInteger&gt;(new BigInteger(key), new BigInteger(value)); items.add(en); } } catch (Exception e) { e.printStackTrace(); } ItemCompare compare = new ItemCompare(); MergeSort sorter = new MergeSort(); sorter.sort(items, compare); System.out.println("Done!"); } </code></pre>
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    1. USMadeInJapan
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    1. COis giving the jvm more memory an option (Xms=<big number>m -Xmx=<big number>m)?
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      1. USmconlin
    2. CO@mconlin it is an option but ill advised
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      1. USTdorno
    3. COI would think resource allocation as advised or ill advised is up to the original posters needs and situation. No one rule can always be right.
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      1. USmconlin
 

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