這個日誌是什麼意思？

當我的應用程序正在執行時（流量很大），我在錯誤日誌中看到了這一點，但我什至不明白它是關於什麼的。我想它正在優化一些配置，但我需要更正式的解釋。

App 13214 stderr: Trying:
App 13214 stderr:   zc = 9  zm = 9  zs = 0  f = 0
App 13214 stderr:       IDAT size = 5698
App 13214 stderr:   zc = 9  zm = 8  zs = 0  f = 0
App 13214 stderr:       IDAT size = 5698
App 13214 stderr:   zc = 9  zm = 9  zs = 1  f = 0
App 13214 stderr:       IDAT size = 5561
App 13214 stderr:   zc = 9  zm = 8  zs = 1  f = 0
App 13214 stderr:       IDAT size = 5561
App 13214 stderr:   zc = 1  zm = 9  zs = 2  f = 0
 zc = 1  zm = 8  zs = 2  f = 0
 zc = 9  zm = 9  zs = 3  f = 0
 zc = 9  zm = 8  zs = 3  f = 0
 zc = 9  zm = 9  zs = 0  f = 1
 zc = 9  zm = 8  zs = 0  f = 1
 zc = 9  zm = 9  zs = 1  f = 1
 zc = 9  zm = 8  zs = 1  f = 1
 zc = 1  zm = 9  zs = 2  f = 1
 zc = 1  zm = 8  zs = 2  f = 1
 zc = 9  zm = 9  zs = 3  f = 1
 zc = 9  zm = 8  zs = 3  f = 1
 zc = 9  zm = 9  zs = 0  f = 2
 zc = 9  zm = 8  zs = 0  f = 2
 zc = 9  zm = 9  zs = 1  f = 2
 zc = 9  zm = 8  zs = 1  f = 2
 zc = 1  zm = 9  zs = 2  f = 2
 zc = 1  zm = 8  zs = 2  f = 2
 zc = 9  zm = 9  zs = 3  f = 2
 zc = 9  zm = 8  zs = 3  f = 2
 zc = 9  zm = 9  zs = 0  f = 3
 zc = 9  zm = 8  zs = 0  f = 3
 zc = 9  zm = 9  zs = 1  f = 3
 zc = 9  zm = 8  zs = 1  f = 3
 zc = 1  zm = 9  zs = 2  f = 3
 zc = 1  zm = 8  zs = 2  f = 3
 zc = 9  zm = 9  zs = 3  f = 3
 zc = 9  zm = 8  zs = 3  f = 3
 zc = 9  zm = 9  zs = 0  f = 4
 zc = 9  zm = 8  zs = 0  f = 4
 zc = 9  zm = 9  zs = 1  f = 4
 zc = 9  zm = 8  zs = 1  f = 4
 zc = 1  zm = 9  zs = 2  f = 4
 zc = 1  zm = 8  zs = 2  f = 4
 zc = 9  zm = 9  zs = 3  f = 4
 zc = 9  zm = 8  zs = 3  f = 4
 zc = 9  zm = 9  zs = 0  f = 5
 zc = 9  zm = 8  zs = 0  f = 5
 zc = 9  zm = 9  zs = 1  f = 5
 zc = 9  zm = 8  zs = 1  f = 5
 zc = 1  zm = 9  zs = 2  f = 5
 zc = 1  zm = 8  zs = 2  f = 5
 zc = 9  zm = 9  zs = 3  f = 5
 zc = 9  zm = 8  zs = 3  f = 5

optipng這是用於縮小 PNG 圖像的實用程序的詳細輸出。--quiet您可以使用該選項抑制此輸出。儘管您的一顆寶石可能正在呼叫它，但您幾乎無法控制它是否通過了該選項。

引用自：https://serverfault.com/questions/577264