     params.max_frag_len  = uint_option(options, "maxins",           init ? 500u    : params.max_frag_len);          // paired-end maximum fragment length
 
     // the maximum batch of reads processed in parallel
-    params.max_batch_size = uint_option(options, "max-batch-size",  init ? 64u*1024u : params.max_batch_size );   // maximum batch size
+    params.max_batch_size = uint_option(options, "max-batch",  init ? 64u*1024u : params.max_batch_size );   // maximum batch size
 
     // internal controls
     params.scoring_window   =       uint_option(options, "scoring-window",   init ? 32u        : params.scoring_window);       // scoring window size

    cudaMemGetInfo(&free, &total);
    log_stats(stderr, "  device has %ld of %ld MB free\n", free/1024/1024, total/1024/1024);

    uint32 BATCH_SIZE = params.max_batch_size*1024;

    for (BATCH_SIZE = 1024*1024; BATCH_SIZE >= 16*1024; BATCH_SIZE /= 2)
    {
        // leave some guard band of free memory
        const uint32 guard_band = 512*1024*1024;

    size_t free, total;
    cudaMemGetInfo(&free, &total);
    log_stats(stderr, "  device has %ld of %ld MB free\n", free/1024/1024, total/1024/1024);

    uint32 BATCH_SIZE;

    for (BATCH_SIZE = params.max_batch_size*1024; BATCH_SIZE >= 16*1024; BATCH_SIZE /= 2)
    {
        // leave some guard band of free memory
        const uint32 guard_band = 512*1024*1024;
