[syslinux] PXERETRY directive

[Gene Cumm]

On Wed, Apr 27, 2016 at 6:56 AM, Geert Stappers via Syslinux
<syslinux at zytor.com> wrote:
> On Wed, Apr 27, 2016 at 12:43:37PM +0200, Geert Stappers via Syslinux wrote:
>> On Wed, Apr 27, 2016 at 06:23:38AM -0400, Gene Cumm via Syslinux wrote:
>> > On Thu, Apr 21, 2016 at 10:30 PM, Ady via Syslinux <syslinux at zytor.com> wrote:
>> > > Would someone please be so kind to explain / describe the PXERETRY
>> > > directive?
>> >
>> > $ git grep -ni pxeretry
>>
>>  -i   ignore case     ("thanks" said the person who exact case matching search )
>   -i   ignore case     ("thanks" said the person who did exact case matching search )

-n is line numbers

grep's -i implementation is rather slow compared to providing a
double-case string, ie "[pP][xX][eE]", but far easier to use.

>> > com32/elflink/ldlinux/readconfig.c:1305:    else if (looking_at(p, "pxeretry"))
>> > com32/elflink/ldlinux/readconfig.c:1306:        PXERetry =
>> > atoi(skipspace(p + 8));
>> >
>> > core/fs/pxe/pxe.c:275:    int i = PXERetry;
>> >
>> >
>> > It's used in pxe_searchdir() to affect how many times it retries to
>> > open a file and added in commit 4f989f247 for 4.03.
>>
>> What is a recommend value for the directive?
>> Has it a default value?

Default is 0 though I'm having difficulty being sure it's actually 0.
Recommended would be 0 unless there's a known issue.  Retries can be
slow though should be a few millliseconds each plus round trip time.
For any TCP transaction, it could easily be 3 RTTs.

>> Currently not reading source, but reading email to help the project
>
> A smooth running project makes making smooth running code fun

Thank you, Geert.

-- 
-Gene