[Buildroot] [PATCH v4 5/5] support/scripts/pkgstats: add CPE reporting

[Ricardo Martincoski <ricardo.martincoski@gmail.com>]

Hello,

On Wed, May 16, 2018 at 08:32 PM, Arnout Vandecappelle wrote:
> On 16-05-18 05:43, Ricardo Martincoski wrote:

[snip]
>> @@ -569,4 +569,5 @@ class CPE:
>>              cpe_file = gzip.GzipFile(fileobj=StringIO(compressed_cpe_file.read())).read()
>> -            print("CPE: Converting xml manifest to dict...")
>> -            self.all_cpes = xmltodict.parse(cpe_file)
>> +            print("CPE: Converting xml manifest to list...")
>> +            tree = ET.fromstring(cpe_file)
>> +            self.all_cpes = [i.get('name') for i in tree.iter('{http://scap.nist.gov/schema/cpe-extension/2.3}cpe23-item')]
> 
>  So after this you get basically the same as after comparison patch 1, right? So
> the xmltodict takes 4 minutes? Or am I missing something?

No. I missed something important and jumped to wrong conclusions.

After adding some simple instrumentation code to display relative timestamps,
the main difference in performance is *not* related to the xml parser used but
it is related to the code used for find() and find_partial().

I didn't performed further testings but it seems related to the use of
startswith as you said.

patch 1:
0:00:00.001015 CPE: Fetching xml manifest...
0:00:03.924777 CPE: Unzipping xml manifest...
0:00:11.672462 CPE: Converting xml manifest to list...
0:00:11.672504 before xmltodict.parse
0:00:36.343417 before append
0:00:36.462400 list created
0:00:36.738042 Build package list ...
0:00:36.875742 Getting package make info ...
0:00:58.543116 Getting package details ...
0:01:00.016925 BR Infra Not building CPE for pkg: [UBOOT]
0:01:07.714094 BR Infra Not building CPE for pkg: [IMX_USB_LOADER]
...
0:08:00.615649 BR Infra Not building CPE for pkg: [INTLTOOL]
0:08:01.243667 BR Infra Not building CPE for pkg: [DOXYGEN]
0:08:02.035463 Calculate stats
0:08:02.042401 Write HTML

patch 2:
0:00:00.000889 CPE: Fetching xml manifest...
0:00:03.640856 CPE: Unzipping xml manifest...
0:00:14.569496 CPE: Converting xml manifest to list...
0:00:14.569541 before ET.fromstring
0:00:21.325842 before list comprehension
0:00:21.609946 list created
0:00:21.612443 Build package list ...
0:00:21.754223 Getting package make info ...
0:00:43.111196 Getting package details ...
0:00:43.828047 BR Infra Not building CPE for pkg: [UBOOT]
0:00:47.125995 BR Infra Not building CPE for pkg: [IMX_USB_LOADER]
...
0:03:46.279893 BR Infra Not building CPE for pkg: [INTLTOOL]
0:03:46.571266 BR Infra Not building CPE for pkg: [DOXYGEN]
0:03:46.892839 Calculate stats
0:03:46.895765 Write HTML

>  Oh, actually, the [... for ... iter...] is also more efficient than
> for...: append() so that could be an effect here as well. But this part of the
> code is only O(#cpe packages) so it shouldn't have that much impact.
> 
>>          except urllib2.HTTPError:package
>> @@ -580,5 +581,5 @@ class CPE:
>>          print("CPE: Searching for partial [%s]" % cpe_str)
>> -        for cpe in self.all_cpes['cpe-list']['cpe-item']:
>> -            if cpe_str in cpe['cpe-23:cpe23-item']['@name']:
>> -                return cpe['cpe-23:cpe23-item']['@name']
>> +        for cpe in self.all_cpes:
>> +            if cpe.startswith(cpe_str):
> 
>  Originally it was 'in' instead of startswith(). Obviously startswith() will be
> more efficient. And also more correct, I guess, or does the partial match not
[snip]

Regards,
Ricardo