database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-08-01 03:47:19 +03:00
Code Activity

multithreaded repair-by-sort code

Browse Source 
parallel read access to IO_CACHE
This commit is contained in:
serg@serg.mysql.com
2002-06-19 23:54:45 +00:00
parent 2874917198
commit 5c83ae3fca
8 changed files with 1255 additions and 497 deletions
Download Patch File Download Diff File Expand all files Collapse all files

118
mysys/mf_iocache.c
View File

@ -85,7 +85,11 @@ init_functions(IO_CACHE* info, enum cache_type type)
info->write_function = 0; /* Force a core if used */
break;
default:
info->read_function = _my_b_read;
info->read_function =
#ifdef THREAD
info->share ? _my_b_read_r :
#endif
_my_b_read;
info->write_function = _my_b_write;
}
@ -127,6 +131,9 @@ int init_io_cache(IO_CACHE *info, File file, uint cachesize,
info->alloced_buffer = 0;
info->buffer=0;
info->seek_not_done= test(file >= 0);
#ifdef THREAD
info->share=0;
#endif
if (!cachesize)
if (! (cachesize= my_default_record_cache_size))
@ -214,7 +221,6 @@ int init_io_cache(IO_CACHE *info, File file, uint cachesize,
DBUG_RETURN(0);
} /* init_io_cache */
/* Wait until current request is ready */
#ifdef HAVE_AIOWAIT
@ -419,6 +425,90 @@ int _my_b_read(register IO_CACHE *info, byte *Buffer, uint Count)
DBUG_RETURN(0);
}
#ifdef THREAD
int init_io_cache_share(IO_CACHE *info, IO_CACHE_SHARE *s, uint num_threads)
{
DBUG_ASSERT(info->type == READ_CACHE);
pthread_mutex_init(& s->mutex, MY_MUTEX_INIT_FAST);
pthread_cond_init (& s->cond, 0);
s->count=num_threads;
s->active=0; /* to catch errors */
info->share=s;
info->read_function=_my_b_read_r;
}
int remove_io_thread(IO_CACHE *info)
{
if (errno=pthread_mutex_lock(& info->share->mutex))
return -1;
if (! info->share->count--)
pthread_cond_signal(& info->share->cond);
pthread_mutex_unlock(& info->share->mutex);
return 0;
}
int _my_b_read_r(register IO_CACHE *info, byte *Buffer, uint Count)
{
my_off_t pos_in_file;
int length,diff_length,read_len;
DBUG_ENTER("_my_b_read_r");
if ((read_len=(uint) (info->read_end-info->read_pos)))
{
DBUG_ASSERT(Count >= read_len); /* User is not using my_b_read() */
memcpy(Buffer,info->read_pos, (size_t) (read_len));
Buffer+=read_len;
Count-=read_len;
}
#define IO_ROUND_UP(X) (((X)+IO_SIZE-1) & ~(IO_SIZE-1))
#define IO_ROUND_DN(X) ( (X) & ~(IO_SIZE-1))
while (Count) {
int cnt, len;
pos_in_file= info->pos_in_file + (uint)(info->read_end - info->buffer);
diff_length= pos_in_file & (IO_SIZE-1);
length=IO_ROUND_UP(Count+diff_length)-diff_length;
length=(length <= info->read_length) ?
length + IO_ROUND_DN(info->read_length - length) :
length - IO_ROUND_UP(length - info->read_length) ;
if (lock_io_cache(info))
{
info->share->active=info;
if (info->seek_not_done) /* File touched, do seek */
VOID(my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)));
len=my_read(info->file,info->buffer, length, info->myflags);
info->read_end=info->buffer + (len == -1 ? 0 : len);
info->error=(len == length ? 0 : len);
info->pos_in_file=pos_in_file;
unlock_io_cache(info);
}
else
{
info->error= info->share->active->error;
info->read_end= info->share->active->read_end;
info->pos_in_file= info->share->active->pos_in_file;
len= (info->error == -1 ? -1 : info->read_end-info->buffer);
}
info->read_pos=info->buffer;
info->seek_not_done=0;
if (info->error)
{
info->error=read_len;
DBUG_RETURN(1);
}
cnt=(len > Count) ? Count : len;
memcpy(Buffer,info->read_pos, (size_t)cnt);
Count -=cnt;
Buffer+=cnt;
read_len+=cnt;
info->read_pos+=cnt;
}
DBUG_RETURN(0);
}
#endif
/*
Do sequential read from the SEQ_READ_APPEND cache
we do this in three stages:
@ -454,7 +544,7 @@ int _my_b_seq_read(register IO_CACHE *info, byte *Buffer, uint Count)
*/
VOID(my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)));
info->seek_not_done=0;
diff_length=(uint) (pos_in_file & (IO_SIZE-1));
/* now the second stage begins - read from file descriptor */
@ -510,7 +600,7 @@ int _my_b_seq_read(register IO_CACHE *info, byte *Buffer, uint Count)
memcpy(Buffer,info->buffer,(size_t) length);
Count -= length;
Buffer += length;
/*
added the line below to make
DBUG_ASSERT(pos_in_file==info->end_of_file) pass.
@ -544,7 +634,7 @@ read_append_buffer:
/*
TODO: figure out if the assert below is needed or correct.
*/
DBUG_ASSERT(pos_in_file == info->end_of_file);
DBUG_ASSERT(pos_in_file == info->end_of_file);
copy_len=min(Count, len_in_buff);
memcpy(Buffer, info->append_read_pos, copy_len);
info->append_read_pos += copy_len;
@ -910,7 +1000,7 @@ int _flush_io_cache(IO_CACHE *info, int need_append_buffer_lock)
if (!(append_cache = (info->type == SEQ_READ_APPEND)))
need_append_buffer_lock=0;
if (info->type == WRITE_CACHE || append_cache)
{
if (info->file == -1)
@ -919,7 +1009,7 @@ int _flush_io_cache(IO_CACHE *info, int need_append_buffer_lock)
DBUG_RETURN((info->error= -1));
}
LOCK_APPEND_BUFFER;
if ((length=(uint) (info->write_pos - info->write_buffer)))
{
pos_in_file=info->pos_in_file;
@ -956,7 +1046,7 @@ int _flush_io_cache(IO_CACHE *info, int need_append_buffer_lock)
info->end_of_file+=(info->write_pos-info->append_read_pos);
DBUG_ASSERT(info->end_of_file == my_tell(info->file,MYF(0)));
}
info->append_read_pos=info->write_pos=info->write_buffer;
UNLOCK_APPEND_BUFFER;
DBUG_RETURN(info->error);
@ -980,6 +1070,18 @@ int end_io_cache(IO_CACHE *info)
IO_CACHE_CALLBACK pre_close;
DBUG_ENTER("end_io_cache");
#ifdef THREAD
/* simple protection against multi-close: destroying share first */
if (info->share)
if (pthread_cond_destroy (& info->share->cond) |
pthread_mutex_destroy(& info->share->mutex))
{
DBUG_RETURN(1);
}
else
info->share=0;
#endif
if ((pre_close=info->pre_close))
(*pre_close)(info);
if (info->alloced_buffer)