[sheepdog] [PATCH v3 2/2] collie: add a new option --progress to "node recovery" for showing recovery progress

[Liu Yuan]

On Fri, Aug 02, 2013 at 05:31:10PM +0900, Hitoshi Mitake wrote:
> At Fri, 2 Aug 2013 16:27:03 +0800,
> Liu Yuan wrote:
> > 
> > On Fri, Aug 02, 2013 at 04:52:06PM +0900, Hitoshi Mitake wrote:
> > > This patch adds a new option --progress (or -P) to the node recovery
> > > subcommand. With this subcommand, users can show a progress of
> > > recovery process.
> > > 
> > > Example:
> > > $ sudo collie node recovery --progress
> > >  99.7 % [==============================================>] 7047 / 7068
> > > 
> > > The denominator (7068 in the above case) indicates a number of entire
> > > object which should be checked. The numerator (7047 in the above case)
> > > indicates a number of objects which is already checked or copied.
> > > 
> > > Signed-off-by: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>
> > > ---
> > > v3:
> > >  - clean coding style
> > > 
> > > v2:
> > >  - make this feature as an option of "node recovery", not a new subcommand
> > >  - clean coding style
> > >  -- renaming recovery_progress_unit() -> get_recovery_progress()
> > > 
> > >  collie/node.c |   91 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> > >  1 file changed, 89 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/collie/node.c b/collie/node.c
> > > index 4230af5..19b5508 100644
> > > --- a/collie/node.c
> > > +++ b/collie/node.c
> > > @@ -13,6 +13,7 @@
> > >  
> > >  static struct node_cmd_data {
> > >  	bool all_nodes;
> > > +	bool recovery_progress;
> > >  } node_cmd_data;
> > >  
> > >  static void cal_total_vdi_size(uint32_t vid, const char *name, const char *tag,
> > > @@ -120,10 +121,92 @@ static int node_info(int argc, char **argv)
> > >  	return EXIT_SUCCESS;
> > >  }
> > >  
> > > +static int get_recovery_state(struct recovery_state *state)
> > > +{
> > > +	int ret;
> > > +	struct sd_req req;
> > > +
> > > +	sd_init_req(&req, SD_OP_STAT_RECOVERY);
> > > +	req.data_length = sizeof(*state);
> > > +
> > > +	ret = collie_exec_req(sdhost, sdport, &req, state);
> > > +	if (ret < 0) {
> > > +		fprintf(stderr, "Failed to execute request\n");
> > > +		return -1;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int node_recovery_progress(void)
> > > +{
> > > +	int result, prev_in_recovery = 0;
> > > +
> > > +	/*
> > > +	 * prev_in_recovery is required for expressing state transition.
> > > +	 * If the variable is 0 and obtained state indicates not in recovery,
> > > +	 * node wasn't doing recovery from first.
> > > +	 */
> > > +
> > > +	/*
> > > +	 * ToDos
> > > +	 *
> > > +	 * 1. Calculate size of actually copied objects.
> > > +	 *    For doing this, not so trivial changes for recovery process are
> > > +	 *    required.
> > > +	 *
> > > +	 * 2. Print remaining physical time.
> > > +	 *    Even if it is not so acculate, the information is helpful for
> > > +	 *    administrators.
> > > +	 */
> > > +
> > > +	do {
> > > +		struct recovery_state rstate;
> > > +
> > > +		result = get_recovery_state(&rstate);
> > > +		if (result < 0)
> > > +			break;
> > > +
> > > +		if (!rstate.in_recovery) {
> > > +			if (prev_in_recovery)
> > > +				/* not an immediate completion */
> > > +				show_progress(rstate.nr_total, rstate.nr_total,
> > > +					true);
> > > +
> > > +			break;
> > > +		}
> > 
> > I don't think we need prev_in_recovery.
> > 
> > if (not_in_recovery) {
> > 	show_progress(total, total, true);
> > 	break;
> > }
> > 
> > Above can both apply to 1) no recovery 2) recovery finishes.
> 
> If we do so, collie prints 100% progress bar even if sheep didn't do
> recovery from first. This is confusing. In addition, show_progress()
> raises an exception of zero division because the value of the total is
> 0.

So with your code, rstate.nr_total can be 0 too? I think you should store
nr_total when you get it first.

Seems that get_recovery_state before the loop would be better solution.

Thanks
Yuan