[sheepdog] [PATCH v3 3/4] sheep: add SD_OP_SYNC_VDI and SD_OP_FLUSH_PEER for writeback cache semantics

[MORITA Kazutaka]

At Wed,  5 Sep 2012 23:31:04 +0900,
Hitoshi Mitake wrote:
> diff --git a/include/internal_proto.h b/include/internal_proto.h
> index 5288823..06f74fa 100644
> --- a/include/internal_proto.h
> +++ b/include/internal_proto.h
> @@ -65,6 +65,8 @@
>  #define SD_OP_INFO_RECOVER 0xAA
>  #define SD_OP_GET_VDI_COPIES 0xAB
>  #define SD_OP_COMPLETE_RECOVERY 0xAC
> +#define SD_OP_SYNC_VDI 0xAD
> +#define SD_OP_FLUSH_PEER 0xAE

Should be SD_OP_SYNC_PEER?

If yes, rename default_flusht to default_sync, peer_flush to
peer_sync, and so on.


> diff --git a/sheep/sheep.c b/sheep/sheep.c
> index e1434cf..f960faf 100644
> --- a/sheep/sheep.c
> +++ b/sheep/sheep.c
> @@ -49,9 +49,9 @@ static struct option const long_options[] = {
>  	{"stdout", no_argument, NULL, 'o'},
>  	{"port", required_argument, NULL, 'p'},
>  	{"disk-space", required_argument, NULL, 's'},
> -	{"enable-cache", required_argument, NULL, 'w'},
>  	{"zone", required_argument, NULL, 'z'},
>  	{"pidfile", required_argument, NULL, 'P'},
> +	{"cache", required_argument, NULL, 'w'},
>  	{NULL, 0, NULL, 0},
>  };
>  
> @@ -78,9 +78,9 @@ Options:\n\
>    -p, --port              specify the TCP port on which to listen\n\
>    -P, --pidfile           create a pid file\n\
>    -s, --disk-space        specify the free disk space in megabytes\n\
> -  -w, --enable-cache      enable object cache and specify the max size (M) and mode\n\
>    -y, --myaddr            specify the address advertised to other sheep\n\
>    -z, --zone              specify the zone id\n\
> +  -w, --cache             specify the cache type\n\

"-w, --write-cache" looks better to me.


> +static void object_cache_set(char *s)
> +{
> +	const char *header = "object:";
> +	int len = strlen(header);
> +	char *size, *p;
> +	int64_t cache_size;
> +
> +	if (strncmp(s, header, len))
> +		goto err;
> +
> +	size = s + len;
> +	cache_size = strtol(size, &p, 10);
> +	if (size == p || cache_size < 0 || UINT64_MAX < cache_size)
> +		goto err;
> +
> +	sys->enable_write_cache = 1;
> +	sys->cache_size = cache_size * 1024 * 1024;

Should be renamed to 'enable_object_cache' and 'object_cache_size' to
avoid confusion.

> +
> +	return;
> +err:
> +	fprintf(stderr, "Invalid object cache option '%s': "
> +		"size must be an integer between 0 and %lu\n",
> +		s, UINT64_MAX);
> +	exit(1);
> +}
> +
> +static void disk_cache_set(char *s)
> +{
> +	if (strcmp(s, "disk")) {
> +		fprintf(stderr, "invalid disk cache option: %s\n", s);
> +		exit(1);
> +	}
> +
> +	sys->store_writeback = 1;

disk_write_cache looks better to me.

Thanks,

Kazutaka