ASYNC_IO_COMPLETION wait stats measure the time SQL Server waits for big file jobs: backups, restores and new data file space. On Night 11 at the Clipboard Diner, the night truck and a freshly painted shelf show which part is normal and which part you can remove. One setting, instant file initialization, removes most of the avoidable waiting.
SQL Server emergency? Email pinal@sqlauthority.com with URGENT in the subject line.
IO_COMPLETION Wait Stats: Spills, Sorts and File Growth
IO_COMPLETION wait stats measure queries waiting on disk work that isn’t a normal data page read, such as sorts and hashes that spill to tempdb. On Night 10 at the Clipboard Diner, a sheet cake for twelve turns out to be for sixty. Learn why spills happen, how to find them, and what SQL Server 2022 changed for log file growth.
Sorting Correctly: Collation and ORDER BY
Collation and ORDER BY decide case, accent, and text-number order; choose rules explicitly when one report needs different sorting.
PAGEIOLATCH Wait Stats: Waiting for Data From Disk
PAGEIOLATCH wait stats measure queries waiting while data pages are read from disk into memory. On Night 9 at the Clipboard Diner, the prep counter is too small for the menu and the cooks keep sending for things from the basement. Learn the two causes, how to read file latency per file, and the fixes in order.
SOS_SCHEDULER_YIELD Wait Stats: Reading CPU Pressure
SOS_SCHEDULER_YIELD wait stats count the moments a query gives up the CPU after its 4 ms turn and waits to get it back. On Night 8 at the Clipboard Diner, every cook steps on and off the burners all night. Learn when this wait is harmless, when it means CPU pressure, and how to find the queries that burn the most CPU.
SQL SERVER – Automation Process Good or Ugly
Is an automation process good or ugly? For T-SQL Tuesday I list the good side of automation in SQL Server, like SQL Agent jobs, and ask for your help.
Parallelism Wait Stats: Tuning MAXDOP and Cost Threshold
Parallelism wait stats drop when two settings fit your server: cost threshold for parallelism decides which queries go parallel, and MAXDOP decides how many threads they get. On Night 7 at the Clipboard Diner, Casey writes two house rules for big parties. Then the kitchen starts learning on its own, the way DOP feedback does in SQL Server 2025 Enterprise.
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Who We Are
Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 24 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.
Pinal has authored 19 books and 125 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.
Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).
Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.
Shaivi Pinalkumar Dave is a book author and a women’s artistic gymnast.

