<div dir="ltr">Depends on his use case. The only way he is seeing 4-5:1 CR is if there are a lot of 0-filled pages being swapped out (those just get thrown away completely). Firefox is known to request tons of RAM this way, of which it regularly ends up not using most.<div>On a more sane load, you will typically achieve about 2:1.</div><div><br></div><div>Realistically, if you have 1GB of RAM and give 512MB to zram, that gives you about 512MB of uncompressed RAM and 1GB of somewhat slower compressed RAM that is still way faster than swapping.</div></div><br><div class="gmail_quote"><div dir="ltr">On Fri, Oct 12, 2018 at 5:46 PM Robert Moskowitz <<a href="mailto:rgm@htt-consult.com">rgm@htt-consult.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
It is now built into Fedora29-arm. That is where Mark got the
source and the systemd support. Yes, earlier many just used it.
Now Fedora-arm is based on it.<br>
<br>
On the Fedora-arm list, Peter Robinson has said he is seeing 4-5
fold compression. That means that if you use a factor of 2 and have
a 1GB memory SOC, that is effectively 2.5GB ram. Or use a factor of
4 for effectively 1.75GB and less 'swapping'. So you can use your
1GB duo core system more effectively, even if you currently have
swap on a HD or SSD sata or USB attached.<br>
<br>
<br>
<div class="m_-1759468752887870240moz-cite-prefix">On 10/12/18 12:25 PM, Gordan Bobic
wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">Because swapping to SD card is slow, swapping to
zram is fast, and zram only takes about 1/2 of the RAM that it
provides.
<div>It's basically RAM compression.</div>
<div>It works and makes a positive difference, even without
exceedingly slow storage.</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr">On Fri, Oct 12, 2018 at 5:16 PM Fred Gleason <<a href="mailto:fredg@paravelsystems.com" target="_blank">fredg@paravelsystems.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word">On Oct 7, 2018, at 07:58,
Robert Moskowitz <<a href="mailto:rgm@htt-consult.com" target="_blank">rgm@htt-consult.com</a>>
wrote:
<div><br>
<div>
<blockquote type="cite">
<div><span style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;float:none;display:inline!important">I
have very recently learned about zram-swap.
Fedora-29-arm is using it. It supposedly makes a
considerable difference even over HD swap.</span><br style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px">
<br style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px">
<span style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;float:none;display:inline!important">Since
many (potential) users of Centos-arm do not have a
ready HD, perhaps we can switch the image from a
physical partition to zram? Or at least
instructions to change to this on the wiki.</span></div>
</blockquote>
</div>
<br>
</div>
<div>Not to be utterly naive, but why is swap required on
such systems at all? To take core RAM and repurpose it as
swap would seem to vitiate the entire point of having a
virtual memory subsystem in the first place.</div>
<div><br>
</div>
<div>Cheers!</div>
<div><br>
</div>
<div><br>
</div>
<div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|----------------------------------------------------------------------|</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|
Frederick F. Gleason, Jr. | Chief
Developer |</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|
| Paravel Systems
|</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|----------------------------------------------------------------------|</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|
Perfection is reached, not when there is no longer
anything to add, |</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|
but when there is no longer anything to take away.
|</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|
-- Antoine de
Saint-Exupery |</span></div>
<div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">|----------------------------------------------------------------------|</span></div>
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