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    <div class="moz-cite-prefix">On 11/4/25 05:03, Atiq Rahman wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CABC65rNDuixz6r_i09KPhpVaoKykmD_qe9u6yTejQZamSTo-TQ@mail.gmail.com">
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        <div>Hi,<br>
        </div>
        <div>When I am copying over files to the zfs dataset on an
          external HDD, the speed is one third of what it is over exFAT.
          This is zfs to zfs copy which is basically way slower than zfs
          to exFAT.<br clear="all">
        </div>
        <div><br>
        </div>
        <div>This was my zpool create command on the external drive,</div>
        <div><br>
        </div>
        <div>```</div>
        <div>
          <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">zpool
                create -o ashift=12 -O compression=lz4 -o autotrim=off
                -O mountpoint=none -O atime=off -O dnodesize=auto
                hyperspace /dev/dsk/c4t0d0</span></code></div>
        </div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">```</span></code></div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m"><br>
            </span></code></div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m"><span
                style="font-family:Arial,Helvetica,sans-serif">And, this
                is how the dataset was created:</span></span></code></div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m"><br>
            </span></code></div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">```</span></code></div>
        <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-sql"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">
              <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-javascript"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">zfs
                    create -o recordsize=1M -o normalization=formD -O
                    mountpoint=/media hyperspace/media</span></code></div>
              <div><code
class="gmail-listtype-code gmail-listindent1 gmail-list-code1 gmail-lang-javascript"><span
class="gmail-author-d-1gg9uz65z1iz85zgdz68zmqkz84zo2qovvz79zvrz83ztoxeg9z71zxaez67zz79zxz83zz69zj4z83zvmz76zz69zz69zz78z1m">```</span></code></div>
            </span></code></div>
        <div><br>
        </div>
        <div>I know zfs has journaling overhead. But, is it possible to
          set certain zfs properties to improve the transfer speed?</div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>
          <div dir="ltr" class="gmail_signature"
            data-smartmail="gmail_signature">
            <div dir="ltr">
              <p class="MsoNormal" style="vertical-align:baseline"><a
                  name="SignatureSanitizer__MailAutoSig"
                  moz-do-not-send="true"><span
                    style="font-size:10pt;font-family:Roboto">Best!</span></a></p>
              <p class="MsoNormal" style="vertical-align:baseline"><a
                  name="SignatureSanitizer__MailAutoSig"
                  moz-do-not-send="true"><span
                    style="font-size:10pt;font-family:Roboto">Atiq</span></a></p>
            </div>
          </div>
        </div>
      </div>
      <br>
      <fieldset class="moz-mime-attachment-header"></fieldset>
      <pre wrap="" class="moz-quote-pre">_______________________________________________
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</pre>
    </blockquote>
    <p>Hello Atiq!</p>
    <p>How do you copy, please show the commands (?)</p>
    <p>You may want to investigate the read speed with something like
      zfs send ... > /dev/null</p>
    <p>If you do a zfs send -> receive, a buffer like "mbuffer" may
      help, over network pathes in combination with a compression
      pbzip2, pigz ...</p>
    <p><br>
    </p>
    <p>Regards,</p>
    <p>Stephan</p>
    <p><br>
    </p>
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