[prev in list] [next in list] [prev in thread] [next in thread] 

List:       kde-frameworks-devel
Subject:    Re: Review Request 130084: Add a pair of flags forcing fsync during copy loop
From:       Oswald Buddenhagen <ossi () kde ! org>
Date:       2017-05-05 8:25:13
Message-ID: 20170505082513.2829.71179 () mimi ! kde ! org
[Download RAW message or body]

--===============2750225537895842507==
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit


-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
https://git.reviewboard.kde.org/r/130084/#review103186
-----------------------------------------------------------




src/ioslaves/file/file_unix.cpp (line 112)
<https://git.reviewboard.kde.org/r/130084/#comment68663>

    typo



src/ioslaves/file/file_unix.cpp (line 138)
<https://git.reviewboard.kde.org/r/130084/#comment68664>

    why are you testing hotpluggable? what's the exact definition in this context? technically, any sata \
drive is hotpluggable ...



src/ioslaves/file/file_unix.cpp (line 324)
<https://git.reviewboard.kde.org/r/130084/#comment68665>

    i'd use some parens here to make it more readable.


- Oswald Buddenhagen


On April 17, 2017, 1:27 p.m., KJ Tsanaktsidis wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://git.reviewboard.kde.org/r/130084/
> -----------------------------------------------------------
> 
> (Updated April 17, 2017, 1:27 p.m.)
> 
> 
> Review request for KDE Frameworks, Oswald Buddenhagen and Thiago Macieira.
> 
> 
> Repository: kio
> 
> 
> Description
> -------
> 
> When copying a large-ish file (~1-2GB) from very fast storage to very slow storage (e.g. an NVME SSD to \
> a cheap USB flash drive) on a machine with lots of RAM, Dolphin displays a progress bar which finishes \
> in a fraction of a second (i.e. as fast as it takes to read the source file into the Linux page cache). \
> Unmounting the drive then of course takes a long time, with only an indeterminate spinner. 
> This patch adds an option to force fsync during copy jobs, so that the copy progress bar measures how \
> long it will take to actually copy the file to the destination. 
> I've added two flags - Fsync and FsyncCrossFilesystem - to the JobEnum flag. The former will cause all \
> copy operations to fsync during the copy loop, whilst the latter will only fsync copies that are across \
> different filesystems. 
> If this patch gets OK'd, I have another patch which adds support for this into the appropriate places \
> in Dolphin. I would think that at least FsyncCrossFilesystem should be the default, but Fsync always \
> might be a little heavy handed. At the least fsync'ing cross-filesystem copies ensures that the unmount \
> won't take forever. 
> 
> Diffs
> -----
> 
> src/ioslaves/file/CMakeLists.txt b9132ced9d4a08b2cf9f9bbbaa3bd43f026c6469 
> src/ioslaves/file/ConfigureChecks.cmake 5a83d1b9fbe90c851c774e3b467468d93b5a2bd4 
> src/ioslaves/file/config-kioslave-file.h.cmake 372f79d01ad4597aae0b2ae62627648fe7680b64 
> src/ioslaves/file/file_unix.cpp 3c1b9927e3dd2d0134f77caec6e6b24a0356d26f 
> 
> Diff: https://git.reviewboard.kde.org/r/130084/diff/
> 
> 
> Testing
> -------
> 
> Tested the patch with KDE/Dolphin on Arch Linux, which is version 5.32.0. The diff applies cleanly to \
> master so I assume there shouldn't be any issues there, but I've not actually checked that. As \
> advertised, copying a file to USB flash storage now displays an accurate progress bar. 
> I experimented with how often fsync should be called on my hardware, and I found calling it every ~1M \
> copied caused no decrease in copy performance whilst still providing accurate progress info. That is \
> the setting I've gone with in this patch. I'm open to suggestions on how this could be tuned better \
> though. 
> 
> Thanks,
> 
> KJ Tsanaktsidis
> 
> 


--===============2750225537895842507==
MIME-Version: 1.0
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: 7bit




<html>
 <body>
  <div style="font-family: Verdana, Arial, Helvetica, Sans-Serif;">
   <table bgcolor="#f9f3c9" width="100%" cellpadding="12" style="border: 1px #c9c399 solid; \
border-radius: 6px; -moz-border-radius: 6px; -webkit-border-radius: 6px;">  <tr>
     <td>
      This is an automatically generated e-mail. To reply, visit:
      <a href="https://git.reviewboard.kde.org/r/130084/">https://git.reviewboard.kde.org/r/130084/</a>
     </td>
    </tr>
   </table>
   <br />











<div>



<table width="100%" border="0" bgcolor="white" style="border: 1px solid #C0C0C0; border-collapse: \
collapse; margin: 2px padding: 2px;">  <thead>
  <tr>
   <th colspan="4" bgcolor="#F0F0F0" style="border-bottom: 1px solid #C0C0C0; font-size: 9pt; padding: \
4px 8px; text-align: left;">  <a \
href="https://git.reviewboard.kde.org/r/130084/diff/2/?file=494464#file494464line112" style="color: \
black; font-weight: bold; text-decoration: underline;">src/ioslaves/file/file_unix.cpp</a>  <span \
style="font-weight: normal;">

     (Diff revision 2)

    </span>
   </th>
  </tr>
 </thead>



 
 

 <tbody>

  <tr>
    <th bgcolor="#b1ebb0" style="border-right: 1px solid #C0C0C0;" align="right"><font \
size="2"></font></th>  <td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; \
margin: 0; "></pre></td>  <th bgcolor="#b1ebb0" style="border-left: 1px solid #C0C0C0; border-right: 1px \
solid #C0C0C0;" align="right"><font size="2">112</font></th>  <td bgcolor="#c5ffc4" width="50%"><pre \
style="font-size: 8pt; line-height: 140%; margin: 0; ">        <span class="c1">// I suppose it could \
have just been removed (althouth there isn&#39;t much</span></pre></td>  </tr>

 </tbody>

</table>

 <div style="margin-left: 2em;">

  <pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: \
-o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: \
inherit;white-space: inherit;">typo</p></pre>  </div>
</div>
<br />

<div>



<table width="100%" border="0" bgcolor="white" style="border: 1px solid #C0C0C0; border-collapse: \
collapse; margin: 2px padding: 2px;">  <thead>
  <tr>
   <th colspan="4" bgcolor="#F0F0F0" style="border-bottom: 1px solid #C0C0C0; font-size: 9pt; padding: \
4px 8px; text-align: left;">  <a \
href="https://git.reviewboard.kde.org/r/130084/diff/2/?file=494464#file494464line138" style="color: \
black; font-weight: bold; text-decoration: underline;">src/ioslaves/file/file_unix.cpp</a>  <span \
style="font-weight: normal;">

     (Diff revision 2)

    </span>
   </th>
  </tr>
 </thead>



 
 

 <tbody>

  <tr>
    <th bgcolor="#b1ebb0" style="border-right: 1px solid #C0C0C0;" align="right"><font \
size="2"></font></th>  <td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; \
margin: 0; "></pre></td>  <th bgcolor="#b1ebb0" style="border-left: 1px solid #C0C0C0; border-right: 1px \
solid #C0C0C0;" align="right"><font size="2">138</font></th>  <td bgcolor="#c5ffc4" width="50%"><pre \
style="font-size: 8pt; line-height: 140%; margin: 0; ">    <span class="k">return</span> <span \
class="n">real_storagedrive</span><span class="o">-&gt;</span><span class="n">isRemovable</span><span \
class="p">()</span> <span class="o">||</span> <span class="n">real_storagedrive</span><span \
class="o">-&gt;</span><span class="n">isHotpluggable</span><span class="p">();</span></pre></td>  </tr>

 </tbody>

</table>

 <div style="margin-left: 2em;">

  <pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: \
-o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: \
inherit;white-space: inherit;">why are you testing hotpluggable? what's the exact definition in this \
context? technically, any sata drive is hotpluggable ...</p></pre>  </div>
</div>
<br />

<div>



<table width="100%" border="0" bgcolor="white" style="border: 1px solid #C0C0C0; border-collapse: \
collapse; margin: 2px padding: 2px;">  <thead>
  <tr>
   <th colspan="4" bgcolor="#F0F0F0" style="border-bottom: 1px solid #C0C0C0; font-size: 9pt; padding: \
4px 8px; text-align: left;">  <a \
href="https://git.reviewboard.kde.org/r/130084/diff/2/?file=494464#file494464line324" style="color: \
black; font-weight: bold; text-decoration: underline;">src/ioslaves/file/file_unix.cpp</a>  <span \
style="font-weight: normal;">

     (Diff revision 2)

    </span>
   </th>
  </tr>
 </thead>



 
 

 <tbody>

  <tr>
    <th bgcolor="#b1ebb0" style="border-right: 1px solid #C0C0C0;" align="right"><font \
size="2"></font></th>  <td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; \
margin: 0; "></pre></td>  <th bgcolor="#b1ebb0" style="border-left: 1px solid #C0C0C0; border-right: 1px \
solid #C0C0C0;" align="right"><font size="2">324</font></th>  <td bgcolor="#c5ffc4" width="50%"><pre \
style="font-size: 8pt; line-height: 140%; margin: 0; ">        <span class="k">if</span> <span \
class="p">(</span><span class="n">should_fsync</span> <span class="o">&amp;&amp;</span> <span \
class="n">niters</span> <span class="o">%</span> <span class="mi">128</span> <span class="o">==</span> \
<span class="mi">0</span><span class="p">)</span> <span class="p">{</span></pre></td>  </tr>

 </tbody>

</table>

 <div style="margin-left: 2em;">

  <pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: \
-o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: \
inherit;white-space: inherit;">i'd use some parens here to make it more readable.</p></pre>  </div>
</div>
<br />



<p>- Oswald Buddenhagen</p>


<br />
<p>On April 17th, 2017, 1:27 p.m. CEST, KJ Tsanaktsidis wrote:</p>








<table bgcolor="#fefadf" width="100%" cellspacing="0" cellpadding="12" style="border: 1px #888a85 solid; \
border-radius: 6px; -moz-border-radius: 6px; -webkit-border-radius: 6px;">  <tr>
  <td>

<div>Review request for KDE Frameworks, Oswald Buddenhagen and Thiago Macieira.</div>
<div>By KJ Tsanaktsidis.</div>


<p style="color: grey;"><i>Updated April 17, 2017, 1:27 p.m.</i></p>









<div style="margin-top: 1.5em;">
 <b style="color: #575012; font-size: 10pt;">Repository: </b>
kio
</div>


<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
 <table width="100%" bgcolor="#ffffff" cellspacing="0" cellpadding="10" style="border: 1px solid \
#b8b5a0">  <tr>
  <td>
   <pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: \
-pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: \
inherit;margin: 0;line-height: inherit;white-space: inherit;">When copying a large-ish file (~1-2GB) from \
very fast storage to very slow storage (e.g. an NVME SSD to a cheap USB flash drive) on a machine with \
lots of RAM, Dolphin displays a progress bar which finishes in a fraction of a second (i.e. as fast as it \
takes to read the source file into the Linux page cache). Unmounting the drive then of course takes a \
long time, with only an indeterminate spinner.</p> <p style="padding: 0;text-rendering: inherit;margin: \
0;line-height: inherit;white-space: inherit;">This patch adds an option to force fsync during copy jobs, \
so that the copy progress bar measures how long it will take to actually copy the file to the \
destination.</p> <p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: \
inherit;">I've added two flags - Fsync and FsyncCrossFilesystem - to the JobEnum flag. The former will \
cause all copy operations to fsync during the copy loop, whilst the latter will only fsync copies that \
are across different filesystems.</p> <p style="padding: 0;text-rendering: inherit;margin: 0;line-height: \
inherit;white-space: inherit;">If this patch gets OK'd, I have another patch which adds support for this \
into the appropriate places in Dolphin. I would think that at least FsyncCrossFilesystem should be the \
default, but Fsync always might be a little heavy handed. At the least fsync'ing cross-filesystem copies \
ensures that the unmount won't take forever.</p></pre>  </td>
 </tr>
</table>


<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
<table width="100%" bgcolor="#ffffff" cellspacing="0" cellpadding="10" style="border: 1px solid #b8b5a0">
 <tr>
  <td>
   <pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: \
-pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: \
inherit;margin: 0;line-height: inherit;white-space: inherit;">Tested the patch with KDE/Dolphin on Arch \
Linux, which is version 5.32.0. The diff applies cleanly to master so I assume there shouldn't be any \
issues there, but I've not actually checked that. As advertised, copying a file to USB flash storage now \
displays an accurate progress bar.</p> <p style="padding: 0;text-rendering: inherit;margin: \
0;line-height: inherit;white-space: inherit;">I experimented with how often fsync should be called on my \
hardware, and I found calling it every ~1M copied caused no decrease in copy performance whilst still \
providing accurate progress info. That is the setting I've gone with in this patch. I'm open to \
suggestions on how this could be tuned better though.</p></pre>  </td>
 </tr>
</table>


<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
<ul style="margin-left: 3em; padding-left: 0;">

 <li>src/ioslaves/file/CMakeLists.txt <span style="color: \
grey">(b9132ced9d4a08b2cf9f9bbbaa3bd43f026c6469)</span></li>

 <li>src/ioslaves/file/ConfigureChecks.cmake <span style="color: \
grey">(5a83d1b9fbe90c851c774e3b467468d93b5a2bd4)</span></li>

 <li>src/ioslaves/file/config-kioslave-file.h.cmake <span style="color: \
grey">(372f79d01ad4597aae0b2ae62627648fe7680b64)</span></li>

 <li>src/ioslaves/file/file_unix.cpp <span style="color: \
grey">(3c1b9927e3dd2d0134f77caec6e6b24a0356d26f)</span></li>

</ul>

<p><a href="https://git.reviewboard.kde.org/r/130084/diff/" style="margin-left: 3em;">View Diff</a></p>






  </td>
 </tr>
</table>







  </div>
 </body>
</html>


--===============2750225537895842507==--


[prev in list] [next in list] [prev in thread] [next in thread] 

Configure | About | News | Add a list | Sponsored by KoreLogic