Re: [PATCH 3/3] utils: Deprecate inexact fractional suffix sizes
On 2/4/21 1:07 PM, Eric Blake wrote:
The value '1.1k' is inexact; 1126.4 bytes is not possible, so
we
happen to truncate it to 1126. Our use of fractional sizes is
intended for convenience, but when a user specifies a fraction that is
not a clean translation to binary, truncating/rounding behind their
backs can cause confusion. Better is to deprecate inexact values,
which still leaves '1.5k' as valid, but alerts the user to spell out
their values as a precise byte number in cases where they are
currently being rounded.
And I promptly forgot to save my changes in my editor. Consider this
squashed in:
diff --git i/docs/system/deprecated.rst w/docs/system/deprecated.rst
index c404c3926e6f..8e5e05a10642 100644
--- i/docs/system/deprecated.rst
+++ w/docs/system/deprecated.rst
@@ -154,6 +154,15 @@ Input parameters that take a size value should only
use a size suffix
the value is hexadecimal. That is, '0x20M' is deprecated, and should
be written either as '32M' or as '0x2000000'.
+inexact sizes via scaled fractions (since 6.0)
+''''''''''''''''''''''''''''''''''''''''''''''
+
+Input parameters that take a size value should only use a fractional
+size (such as '1.5M') that will result in an exact byte value. The
+use of inexact values (such as '1.1M') that require truncation or
+rounding is deprecated, and you should instead consider writing your
+unusual size in bytes (here, '1153433' or '1153434' as desired).
+
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Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
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