[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH] docs/xl: Clarify documentation for mem-max and mem-set


  • To: Lars Kurth <lars.kurth@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • From: George Dunlap <george.dunlap@xxxxxxxxxx>
  • Date: Thu, 2 Aug 2018 11:23:59 +0100
  • Autocrypt: addr=george.dunlap@xxxxxxxxxx; prefer-encrypt=mutual; keydata= xsFNBFPqG+MBEACwPYTQpHepyshcufo0dVmqxDo917iWPslB8lauFxVf4WZtGvQSsKStHJSj 92Qkxp4CH2DwudI8qpVbnWCXsZxodDWac9c3PordLwz5/XL41LevEoM3NWRm5TNgJ3ckPA+J K5OfSK04QtmwSHFP3G/SXDJpGs+oDJgASta2AOl9vPV+t3xG6xyfa2NMGn9wmEvvVMD44Z7R W3RhZPn/NEZ5gaJhIUMgTChGwwWDOX0YPY19vcy5fT4bTIxvoZsLOkLSGoZb/jHIzkAAznug Q7PPeZJ1kXpbW9EHHaUHiCD9C87dMyty0N3TmWfp0VvBCaw32yFtM9jUgB7UVneoZUMUKeHA fgIXhJ7I7JFmw3J0PjGLxCLHf2Q5JOD8jeEXpdxugqF7B/fWYYmyIgwKutiGZeoPhl9c/7RE Bf6f9Qv4AtQoJwtLw6+5pDXsTD5q/GwhPjt7ohF7aQZTMMHhZuS52/izKhDzIufl6uiqUBge 0lqG+/ViLKwCkxHDREuSUTtfjRc9/AoAt2V2HOfgKORSCjFC1eI0+8UMxlfdq2z1AAchinU0 eSkRpX2An3CPEjgGFmu2Je4a/R/Kd6nGU8AFaE8ta0oq5BSFDRYdcKchw4TSxetkG6iUtqOO ZFS7VAdF00eqFJNQpi6IUQryhnrOByw+zSobqlOPUO7XC5fjnwARAQABzSRHZW9yZ2UgVy4g RHVubGFwIDxkdW5sYXBnQHVtaWNoLmVkdT7CwYAEEwEKACoCGwMFCwkIBwMFFQoJCAsFFgID AQACHgECF4ACGQEFAlpk2IEFCQo9I54ACgkQpjY8MQWQtG1A1BAAnc0oX3+M/jyv4j/ESJTO U2JhuWUWV6NFuzU10pUmMqpgQtiVEVU2QbCvTcZS1U/S6bqAUoiWQreDMSSgGH3a3BmRNi8n HKtarJqyK81aERM2HrjYkC1ZlRYG+jS8oWzzQrCQiTwn3eFLJrHjqowTbwahoiMw/nJ+OrZO /VXLfNeaxA5GF6emwgbpshwaUtESQ/MC5hFAFmUBZKAxp9CXG2ZhTP6ROV4fwhpnHaz8z+BT NQz8YwA4gkmFJbDUA9I0Cm9D/EZscrCGMeaVvcyldbMhWS+aH8nbqv6brhgbJEQS22eKCZDD J/ng5ea25QnS0fqu3bMrH39tDqeh7rVnt8Yu/YgOwc3XmgzmAhIDyzSinYEWJ1FkOVpIbGl9 uR6seRsfJmUK84KCScjkBhMKTOixWgNEQ/zTcLUsfTh6KQdLTn083Q5aFxWOIal2hiy9UyqR VQydowXy4Xx58rqvZjuYzdGDdAUlZ+D2O3Jp28ez5SikA/ZaaoGI9S1VWvQsQdzNfD2D+xfL qfd9yv7gko9eTJzv5zFr2MedtRb/nCrMTnvLkwNX4abB5+19JGneeRU4jy7yDYAhUXcI/waS /hHioT9MOjMh+DoLCgeZJYaOcgQdORY/IclLiLq4yFnG+4Ocft8igp79dbYYHkAkmC9te/2x Kq9nEd0Hg288EO/OwE0EVFq6vQEIAO2idItaUEplEemV2Q9mBA8YmtgckdLmaE0uzdDWL9To 1PL+qdNe7tBXKOfkKI7v32fe0nB4aecRlQJOZMWQRQ0+KLyXdJyHkq9221sHzcxsdcGs7X3c 17ep9zASq+wIYqAdZvr7pN9a3nVHZ4W7bzezuNDAvn4EpOf/o0RsWNyDlT6KECs1DuzOdRqD oOMJfYmtx9hMzqBoTdr6U20/KgnC/dmWWcJAUZXaAFp+3NYRCkk7k939VaUpoY519CeLrymd Vdke66KCiWBQXMkgtMGvGk5gLQLy4H3KXvpXoDrYKgysy7jeOccxI8owoiOdtbfM8TTDyWPR Ygjzb9LApA8AEQEAAcLBZQQYAQoADwIbDAUCWmTXMwUJB+tP9gAKCRCmNjwxBZC0bb+2D/9h jn1k5WcRHlu19WGuH6q0Kgm1LRT7PnnSz904igHNElMB5a7wRjw5kdNwU3sRm2nnmHeOJH8k Yj2Hn1QgX5SqQsysWTHWOEseGeoXydx9zZZkt3oQJM+9NV1VjK0bOXwqhiQyEUWz5/9l467F S/k4FJ5CHNRumvhLa0l2HEEu5pxq463HQZHDt4YE/9Y74eXOnYCB4nrYxQD/GSXEZvWryEWr eDoaFqzq1TKtzHhFgQG7yFUEepxLRUUtYsEpT6Rks2l4LCqG3hVD0URFIiTyuxJx3VC2Ta4L H3hxQtiaIpuXqq2D4z63h6vCx2wxfZc/WRHGbr4NAlB81l35Q/UHyMocVuYLj0llF0rwU4Aj iKZ5qWNSEdvEpL43fTvZYxQhDCjQTKbb38omu5P4kOf1HT7s+kmQKRtiLBlqHzK17D4K/180 ADw7a3gnmr5RumcZP3NGSSZA6jP5vNqQpNu4gqrPFWNQKQcW8HBiYFgq6SoLQQWbRxJDHvTR YJ2ms7oCe870gh4D1wFFqTLeyXiVqjddENGNaP8ZlCDw6EU82N8Bn5LXKjR1GWo2UK3CjrkH pTt3YYZvrhS2MO2EYEcWjyu6LALF/lS6z6LKeQZ+t9AdQUcILlrx9IxqXv6GvAoBLJY1jjGB q+/kRPrWXpoaQn7FXWGfMqU+NkY9enyrlw==
  • Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>, Wei Liu <wei.liu2@xxxxxxxxxx>, Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>, "Tim \(Xen.org\)" <tim@xxxxxxx>, Julien Grall <julien.grall@xxxxxxx>, Jan Beulich <jbeulich@xxxxxxxx>, Ian Jackson <Ian.Jackson@xxxxxxxxxx>
  • Delivery-date: Thu, 02 Aug 2018 10:24:12 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
  • Openpgp: preference=signencrypt

On 08/01/2018 05:16 PM, Lars Kurth wrote:
> 
> 
> On 01/08/2018, 16:41, "George Dunlap" <george.dunlap@xxxxxxxxxx> wrote:
> 
>     mem-set is the primary command that users will need to use and
>     understand.  Move it first, and clarify the wording; also specify that
>     you can't set the target higher than maxmem from the domain config.
>     
>     mem-max is actually a pretty useless command at the moment.  Clarify
>     that users are not expected to use it; and document all of its quirky
>     behavior.
>     
>     Signed-off-by: George Dunlap <george.dunlap@xxxxxxxxxx>
>     ---
>     I'm actully somewhat tempted to take out the entry for mem-max
>     entirely -- it's not at all clear to me what anyone would use it for,
>     and it's only likely to confuse people.
> 
> Should it be deprecated, if it isn't useful?
>     
>     CC: Ian Jackson <ian.jackson@xxxxxxxxxx>
>     CC: Wei Liu <wei.liu2@xxxxxxxxxx>
>     CC: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
>     CC: Jan Beulich <jbeulich@xxxxxxxx>
>     CC: Tim Deegan <tim@xxxxxxx>
>     CC: Konrad Wilk <konrad.wilk@xxxxxxxxxx>
>     CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
>     CC: Julien Grall <julien.grall@xxxxxxx>
>     CC: Lars Kurth <lars.kurth@xxxxxxxxxx>
>     ---
>      docs/man/xl.pod.1.in | 72 ++++++++++++++++++++++++++++++--------------
>      1 file changed, 50 insertions(+), 22 deletions(-)
>     
>     diff --git a/docs/man/xl.pod.1.in b/docs/man/xl.pod.1.in
>     index b74764dcd3..1d3dabf185 100644
>     --- a/docs/man/xl.pod.1.in
>     +++ b/docs/man/xl.pod.1.in
>     @@ -393,40 +393,68 @@ less utilized than a high CPU workload.  Consider 
> yourself warned.
>      
>      =back
>      
>     -=item B<mem-max> I<domain-id> I<mem>
>     +=item B<mem-set> I<domain-id> I<mem>
>      
>     -Specify the maximum amount of memory the domain is able to use, 
> appending 't'
>     -for terabytes, 'g' for gigabytes, 'm' for megabytes, 'k' for kilobytes 
> and 'b'
>     -for bytes.
>     +Set the target for the domain's balloon driver.  Append 't' for
> 
> I would say Use instead of Append: if you are not a native speaker you could
> be misled that the command appends memory.

I'm afraid 'use' doesn't tell me what to do -- `set-max A t`? `set-max A
2048 t`?  `set-max A t2048`?

What about making a paragraph break and changing it to:

"The default unit is kiB.  Add 't' to specify TiB, 'g' for GiB, 'm' for
MiB, and 'b' for bytes (e.g., 2048m)."

Alternate we could say `I<mem>[<unit>]`, but that seems to be getting a
little clunky.

>     +terabytes, 'g' for gigabytes, 'm' for megabytes, 'k' for kilobytes
>     +and 'b' for bytes.
>      
>     -The mem-max value may not correspond to the actual memory used in the
>     -domain, as it may balloon down its memory to give more back to the OS.
>     +This must be less than the initial B<maxmem> parameter in the domain's
>     +configuration.
> 
> What happens if it is bigger? Will you get an error, or will the system 
> likely 
> crash?

libxl will return an error.  It's never OK for a command for which we
have a precise limit to crash the system.  (NB the WARNING at the bottom
of this section, about not having a clear lower limit.)

> Reviewed-by: lars.kurth@xxxxxxxxxx

Thanks

 -George

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.