Making your calendar half full

During last 2 weeks, I found my calendar was really full, many back to back meetings. I feel busy but not productive.
I found the biggest problem is hard to deal with unplanned things: sometime a developer asked for help, but I was not available at that time according to my calendar; sometime when a meeting need to change, but due to hard to find another time, it had to be cancelled or delay to next week; sometime I found an issue and want to discuss with my Product owner, but she was not available, we have to wait until next week to discuss it.
So making my calendar full is really harmful:

• it is hard to respond to change,
• hard to solve the problem quickly,
• making co-location less useful if everyone is busy with doing different things.
• it focus on activity not outcome, it violates the Scrum's "inspect and adapt" principle.

In future I decide to change my strategy, instead of making me busy, I will try to make my calenar half full:

• only half of my time can be scheduled for meeting in the morning;
• only half of my time can be scheduled for meeting in the afternoon;
• try not to schedule back to back meetings 

Also I will encourage other team member doing the same thing, especially product owner and people with shared roles like me.
and also our scrum team can also considering make the board half full.
I hope it will help me:

• will be more responsive to unexpected situations;
• will have less waiting time on fixing the problems;
• will be more adaptive and more focused;
• will be easier to coordinate with other team members if they are doing the same thing;
• improve the collaboration;
• help me focus more on effectiveness instead of efficiency;
• have more slack time, so I can focus more on learning and researching.