Re: Speeding up wineserver syncronization objects with shared memory

[David Howells]

> I'll have to write a small program to collect some statistics:-)

Okay, I did a quick and dirty program to do that. It looked through the
following products that I've got installed:

	Win2000 sp1
	MSDEV 98
	MS Office 2000

Using the following command:

      	find  /fs/win2000/WINNT \
              "/fs/win2000/Program Files/Microsoft Visual Studio" \
	      "/fs/win2000/Program Files/Microsoft Office" -type f |
	./scandll

And came up with the following statistics:

	files accessed          : 3985
	valid PE images         : 1752
	- libraries             : 1280
	  - badly VM aligned    : 20
	  - standard image base : 42
	  - specific image base : 1218
	  - file align by sector: 976
	  - file align by page  : 284
	- executables           : 472
	  - badly VM aligned    : 133
	  - standard image base : 70
	  - specific image base : 269
	  - file align by sector: 287
	  - file align by page  : 52

I've attached the program I used.

As you can see, most DLLs actually have their image base set manually to avoid
conflicts. Also a lot of EXEs have it set too... presumably so that they can
also be used as DLLs.

However! the majority of DLLs and EXEs are sector-aligned (512) in the files,
not page-aligned (4096).

David


/* scandll.c: scan DLLs and EXEs
 *
 * Copyright (c) 2001   David Howells (dhowells(a)redhat.com).
 */
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <linux/types.h>

typedef __u8				BOOL, BYTE;
typedef __u16				WORD;
typedef __u32				DWORD, UINT;

#define PAGE_SIZE 4096

#define _H_229A4E44_C7CC_11D4_8F92_0000C0005742 /* skip section.h */
#include "pefile.h"

IMAGE_SECTION_HEADER sechdr;
IMAGE_DOS_HEADER imghdr;
IMAGE_NT_HEADERS nthdr;

int files;
int valid_image;
int dlls;
int exes;
int bad_vm_align[2];
int file_align_sector[2];
int file_align_page[2];
int normal_image_base[2];
int specific_image_base[2];

/*****************************************************************************/
/*
 *
 */
int main(int argc, char **argv)
{
	char fname[1024], *cp;
	int fd = -1, tmp, isexe;

	while (close(fd),
	       fd = -1,
	       fgets(fname,sizeof(fname),stdin)
		)
	{
		cp = strpbrk(fname,"\r\n");
		if (cp)
			*cp = 0;

		fd = open(fname,O_RDONLY);
		if (!fd) {
			if (errno==EISDIR)
				continue;
			perror("open");
			return 1;
		}

		/* get the DOS image header */
		tmp = read(fd,&imghdr,sizeof(imghdr));
		if (tmp<0) {
			if (errno==EISDIR)
				continue;
			perror("read doshdr");
			return 1;
		}
		if (tmp<sizeof(imghdr))
			continue;

		files++;

		if (imghdr.e_magic != IMAGE_DOS_SIGNATURE)
			continue;

		/* get the NT image header */
		lseek(fd,imghdr.e_lfanew,SEEK_SET);
		tmp = read(fd,&nthdr,sizeof(nthdr));
		if (tmp<0) {
			perror("read nthdr");
			return 1;
		}
		if (tmp<sizeof(nthdr))
			continue;

		if (nthdr.Signature != IMAGE_NT_SIGNATURE ||
		    nthdr.FileHeader.Machine != IMAGE_FILE_MACHINE_I386
		    )
			continue;

		if (!(nthdr.FileHeader.Characteristics &
		      IMAGE_FILE_EXECUTABLE_IMAGE))
			continue;

		if (nthdr.OptionalHeader.Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC)
			continue;

		/* okay... it's a valid PE image */
		valid_image++;

		/* is it an EXE file? */
		if (nthdr.FileHeader.Characteristics & IMAGE_FILE_DLL) {
			dlls++;
			isexe = 0;
		}
		else {
			exes++;
			isexe = 1;
		}

		/* check the VM alignment */
		if (!nthdr.OptionalHeader.SectionAlignment ||
		    nthdr.OptionalHeader.SectionAlignment&(PAGE_SIZE-1)
		    ) {
			bad_vm_align[isexe]++;
			continue;
		}

		/* check the file alignment */
		if (!nthdr.OptionalHeader.FileAlignment ||
		    nthdr.OptionalHeader.FileAlignment&(PAGE_SIZE-1)
		    ) {
			file_align_sector[isexe]++;
		}
		else {
			file_align_page[isexe]++;
		}

		/* consider the image base */
		printf("%08x %s\n",nthdr.OptionalHeader.ImageBase,fname);
		if (nthdr.OptionalHeader.ImageBase==0x10000000 ||
		    nthdr.OptionalHeader.ImageBase==0x00400000
			) {
			normal_image_base[isexe]++;
		}
		else {
			specific_image_base[isexe]++;
		}
	}

	printf("files accessed          : %d\n",files);
	printf("valid PE images         : %d\n",valid_image);
	printf("- libraries             : %d\n",dlls);
	printf("  - badly VM aligned    : %d\n",bad_vm_align[0]);
	printf("  - standard image base : %d\n",normal_image_base[0]);
	printf("  - specific image base : %d\n",specific_image_base[0]);
	printf("  - file align by sector: %d\n",file_align_sector[0]);
	printf("  - file align by page  : %d\n",file_align_page[0]);
	printf("- executables           : %d\n",exes);
	printf("  - badly VM aligned    : %d\n",bad_vm_align[1]);
	printf("  - standard image base : %d\n",normal_image_base[1]);
	printf("  - specific image base : %d\n",specific_image_base[1]);
	printf("  - file align by sector: %d\n",file_align_sector[1]);
	printf("  - file align by page  : %d\n",file_align_page[1]);

	return 0;
} /* end main() */
\n",exes);
	printf("  - badly VM aligned    : %d\n",bad_vm_align[1]);
	printf("  - standard image base : %d\n",normal_image_base[1]);
	printf("  - specific image base : %d\n",specific_image_base[1]);
	printf("  - file align by sector: %d\n",file_align_sector[1]);
	printf("  - file align by page  : %d\n",file_align_page[1]);

	return 0;
} /* end main() */