On Tue, 20 Jun 2000, Jan Harkes wrote:
> On Tue, Jun 20, 2000 at 11:19:12AM +0200, ulrich.hahn wrote:
> >
> > While testing metadata performance of coda I encountered a file system
> > full situation. The error occured after creating approx. 7000 files and
> > directories. First I thought this might be a client problem (RVM of venus
> > assuming 16k av. file size) but this did not change with venus cache size.
> >
> > So is there a hard coded limit for directories per volume, or what else
> > did I miss?
>
> What is the size of the directory according to `ls'?
>
> Greg Troxel noted at one point that we don't have indirect directory
> blocks. The directories can thus only become at most 256KB. With 7000
> entries this results in ~37 bytes per entry. 12 bytes are used by flags,
> length and fid, so the average filename size to fill a directory with
> 7000 objects would be about 25 bytes.
>
> I don't know if that includes the \0 character at the end.
>
> Jan
>
The directories itself are small, 2k at most, since they are created
recursive. As the program itself is very small I attached it.
> tb_treetest /coda/tbtree 10
creates 1023 (1013) dirs and 1013 files without problems.
> tb_treetest /coda/tbtree 11
hangs after 2045 dirs and 2035 files
Creating files is still possible, but no more directories.
I then modified the source to create 50 dirs per dir and the coda
hangs at exactly 2045 dirs again, so it doesn´t seem related to
directory depth but simply the number of dirs.
Any clue?
Uli
: Ulrich Hahn email: [EMAIL PROTECTED] :
: Zentrum für Datenverarbeitung Tel: + (49) 07071 29 70315 :
: Universität Tübingen FAX: + (49) 07071 29 5912 :
-----------------------------------------------------------------------
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
static int stepdown(char *root,int tiefe);
static int ndir,nfile;
int main(int argc,char **argv)
{
int tiefe;
int i;
char root[4096];
if ( argc < 3 )
{
fprintf(stderr,"tb_treetest root tiefe\n");
exit(1);
}
/*
create a directory tree starting with <root>. each dir is named by a
number giving the amount of dirs/files contained in that dir. each
file name ends with _f.
*/
if ( !(tiefe = atoi(argv[2])) )
{
exit(0);
}
ndir = 0;
nfile = 0;
sprintf(root,"%s",argv[1]);
if ( mkdir(root,(mode_t)0755) )
{
fprintf(stderr,"can't mkdir %s. %d %s\n",root,errno,strerror(errno));
exit(1);
}
for ( i=0; i<tiefe; i++ )
{
sprintf(root,"%s/%d",argv[1],i);
if ( mkdir(root,(mode_t)0755) )
{
fprintf(stderr,"can't mkdir %s. %d %s\n",root,errno,strerror(errno));
exit(1);
}
if ( chdir(root) )
{
fprintf(stderr,"can't chdir %s. %d %s\n",root,errno,strerror(errno));
exit(1);
}
if ( stepdown(root,i) )
{
fprintf(stderr,"can't stepdown\n");
exit(1);
}
}
fprintf(stdout,"created %d files and %d directories\n",nfile,ndir);
exit(0);
}
static int stepdown(char *root,int tiefe)
{
int i,fd;
char dir[4096],file[4096];
if ( !tiefe )
{
return(0);
}
for ( i=0; i<tiefe; i++ )
{
sprintf(dir,"%d",i);
sprintf(file,"%d_f",i);
if ( (fd = creat(file,(mode_t)0755)) < 0 )
{
fprintf(stderr,"can't create file %s. %d %s\n",file,errno,
strerror(errno));
return(1);
}
close(fd);
nfile++;
if ( mkdir(dir,(mode_t)0755) )
{
fprintf(stderr,"can't mkdir %s. %d %s\n",dir,errno,strerror(errno));
return(1);
}
ndir++;
if ( chdir(dir) )
{
fprintf(stderr,"can't chdir %s. %d %s\n",root,errno,strerror(errno));
return(1);
}
if ( stepdown(dir,i) )
{
fprintf(stderr,"stepdown failed\n");
return(1);
}
if ( chdir("..") )
{
fprintf(stderr,"can't step up. %d %s\n",errno,strerror(errno));
return(1);
}
}
return(0);
}
