<html><head><style>body{font-family:Helvetica,Arial;font-size:13px}</style></head><body style="word-wrap:break-word;line-break:after-white-space"><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;margin:0px;line-height:auto">argh. sorry. Hit the wrong key combo before I was finished.</div> <br> <div id="bloop_sign_1542133307699431936" class="bloop_sign"></div> <p class="airmail_on">On November 13, 2018 at 11:13:31, Matthew Hyclak (<a href="mailto:hyclak@gmail.com">hyclak@gmail.com</a>) wrote:</p><div><blockquote type="cite" class="clean_bq" style="text-align:start;text-indent:0px"><div style="word-wrap:break-word;line-break:after-white-space"><div>Been a while since I did this, but I believe you have to make sure the filesystem you want to be sparse actually contains 0's in the places you'd like to be sparse before creating the sparse file.<br><br><div dir="ltr"><div dir="ltr"><div><span><a href="https://unix.stackexchange.com/questions/44234/clear-unused-space-with-zeros-ext3-ext4">https://unix.stackexchange.com/questions/44234/clear-unused-space-with-zeros-ext3-ext4</a><span class="Apple-converted-space"> </span>looks like a good starting point.</span></div></div></div></div></div></blockquote><div><br></div>Thanks. I had seen that thread. I used zerofree, but it didn’t seem to matter. Because of your link though, I read farther down the page to some information about cp with the ‘—sparse=always’ flag, and some hints about reported size between ls and du.<br>Interestingly enough, I messed around and got the following:<br><div style="word-wrap:break-word;line-break:after-white-space"><p style="font-family:Helvetica,Arial;font-size:13px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-transform:none;white-space:normal;word-spacing:0px;text-decoration:none">cp —sparse=always 16GB_file sparse_file -> 3.7GB, as per du. ls still says it’s 16GB.</p></div></div><p>Right. So 16GB file drops to 3.7GB, says du.</p><p>I then copied (cp) that 3.7GB file back to my Mac without really thinking too much and without any flags, and it ballooned into an 8GB file. No idea why.</p><p>I tried the same copy of the 3.7GB file again (Linux VM -> Mac with cp) adding the —sparse=always flag this time, and it landed as a 4GB file. I think maybe I’m on the right track, or at least getting there. Maybe.</p><div></div></body></html>