If you have BerkeleyDB installed, slip this in at the beginning (where %seq_hash is whatever your big hash is): 
use DB_File;
tie(%seq_hash, "DB_File", "tmp.db", O_RDWR|O_CREAT);

[download]
This will be significantly slower, but should reduce the memory requirements drastically.

In reply to Re (tilly) 2: Any limit to large hashes? by tilly
in thread Any limit to large hashes? by Dogg

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