Date: Thu, 19 Feb 2009 00:13:08 +0100 (CET) From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl> To: Kailash Kailash <kailash.kailash@zscaler.com> Cc: freebsd-questions@freebsd.org Subject: RE: FreeBSD 7.O compiled code is very slow Message-ID: <20090219001251.O40306@wojtek.tensor.gdynia.pl> In-Reply-To: <499c8aca.16098e0a.172b.00f5@mx.google.com> References: <499c7357.14098e0a.1394.ffffda2d@mx.google.com> <20090218224551.X39029@wojtek.tensor.gdynia.pl> <499c8aca.16098e0a.172b.00f5@mx.google.com>
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you install it from ports and use explicitly, everything else still uses
default
On Wed, 18 Feb 2009, Kailash Kailash wrote:
> Can old version of GCC used with BSD 7.0 without facing any compatibility
> problem?
> Thanks,
> Kailash
>
> -----Original Message-----
> From: Wojciech Puchar [mailto:wojtek@wojtek.tensor.gdynia.pl]
> Sent: Wednesday, February 18, 2009 1:46 PM
> To: Kailash Kailash
> Cc: freebsd-questions@freebsd.org
> Subject: Re: FreeBSD 7.O compiled code is very slow
>
> looks like they "improved" gcc. you can install older from ports.
>
> On Wed, 18 Feb 2009, Kailash Kailash wrote:
>
>> I am using FreeBSD 7.0 in 64 BIT mode. Same code compiled on BSD 7.0 runs
>> 50% speed (as expected by CPU and code architecture) compared to BSD 6.2.
>> Here is one real code with binary output. On 3.0 GHz Woodcrest processor,
> I
>> am able to copy from one cache to another cache at the speed of
>> 24Gbytes/second verses 12 Gbytes/second. Any help is appreciated.
>>
>> Thanks,
>>
>> Kailash
>>
>>
>>
>> Source-code:
>>
>> #define BACKWARD_MEMCOPY_WITH_TYPE(dp, sp, len, type)
>> BACKWARD_MEMCOPY((type*)(dp), (const type*)(sp),
>> ((len)+(sizeof(type)-1))/sizeof(type))
>>
>>
>>
>> #define BACKWARD_MEMCOPY(dp, sp, len) \
>>
>> do { \
>>
>> smwbits __len = len; /* must be signed value */ \
>>
>> while (--__len >= 0) \
>>
>> (dp)[__len] = (sp)[__len]; \
>>
>> } while (0)
>>
>>
>>
>> BSD 6.2 code
>>
>> 0x00000000004353b2 <smcli_memory_copy_performance+434>: mov
>> 0x8(%rbp,%rdx,8),%rax
>>
>> 0x00000000004353b7 <smcli_memory_copy_performance+439>: mov
>> %rax,0x48(%r12,%rdx,8)
>>
>> 0x00000000004353bc <smcli_memory_copy_performance+444>: dec %rdx
>>
>> 0x00000000004353bf <smcli_memory_copy_performance+447>: jns 0x4353b2
>> <smcli_memory_copy_performance+434>
>>
>>
>>
>> BSD 7.0 code
>>
>> 0x000000000040cb80 <smcli_memory_copy_performance+272>: mov
>> 0xfffffffffffffff8(%rsi),%rax
>>
>> 0x000000000040cb84 <smcli_memory_copy_performance+276>: mov
>> %rax,0xfffffffffffffff8(%rcx)
>>
>> 0x000000000040cb88 <smcli_memory_copy_performance+280>: sub
>> $0x8,%rsi
>>
>> 0x000000000040cb8c <smcli_memory_copy_performance+284>: sub
>> $0x8,%rcx
>>
>> 0x000000000040cb90 <smcli_memory_copy_performance+288>: sub
>> $0x1,%rdx
>>
>> 0x000000000040cb94 <smcli_memory_copy_performance+292>: jns
>> 0x40cb80 <smcli_memory_copy_performance2+272>
>>
>>
>>
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>
>
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