statvfs() weirdness on alpha (RH-7.2 and CentOS-4.2)

[Sergey Tikhonov]

Sergey Tikhonov wrote:

> Bert de Bruijn wrote:
>
>>
>> Somehow I get very strange readings from statvfs() on Alpha.
>>
>> On Intel
>> $ python
>>
>>>>> import os
>>>>> print os.statvfs('/')
>>>>
>>>>
>> (4096, 4096, 1033182L, 234938L, 182454L, 525888L, 471255L, 471255L, 
>> 0, 255)
>>
>> is correct. "df" with the same blocksize shows the same values
>> $ df -B 4096 /
>> Filesystem           4K-blocks      Used Available Use% Mounted on
>> /dev/hdd1              1033182    798244    182454  82% /
>>
>> But on Alpha
>> $ python
>>
>>>>> import os
>>>>> print os.statvfs('/')
>>>>
>>>>
>> (1024, 1024, 738193209530565, 551989197028090, 469096328178340, 0, 0, 
>> 255, 0, 0)
>>
>> that can't be right, the whole / partition is only 500 MB:
>> $ df -B 1024 /
>> Filesystem           1K-blocks      Used Available Use% Mounted on
>> /dev/sda2               497861    325987    146170  70% /
>>
>> 469096328178340 is not an integer multiple of 146170.
>>
>>
>> BTW, this is not a python problem, perl Filesys::Statvfs has the same 
>> issues.
>>
>>
>> Can anybody shed a light on this ?
>
>
> It seems that it is a problem with python and perl since pure C call 
> to glibc function returns correct values.
> I'll check out since this doen't work in AC2 too.

Got it. The problem is in glibc with statvfs/statvfs64 functions on 
alpha (X86_64 doesn't have such problems).
As far as I understood statvfs64 is mapped to statvfs function on 64 bit 
machines, but "struct statvfs" has 32 bits long
fields on alpha if compiled without any specific 64bits macros and the 
same fields become 64 bits long if compiled with
-D_LARGEILE64_SOURCE -D_FILE_OFFSET_BITS=64. The problem is that glibc 
is compiled with 32 bits long fields,
but packages like python,perl,gnome uses the macros defined above during 
building. I might be wrong in my findings, but after
recompilation python and gnome packages started to work.

For now I changed 64-bits fields in /usr/inclide/bits/typesizes.h 
(__FSBLKCNT64_T_TYPE and __FSFILECNT64_T_TYPE) from
from __S64_TYPE/__U64_TYPE to __S32_TYPE/__S64_TYPE. Making evething 
64-bits would require to rebuild whole AC2 tree. :(

Regards,

-- 
Sergey Tikhonov
Solvo Ltd.
tsv at solvo.ru