ﺍﻷﺼل ﺃﻨﻪ ﻋﻨﺩﻤﺎ ﻴﻁﻠﺏ ﺍﻟﻤﺴﺘﺨﺩﻡ ﺍﻻﺘﺼﺎل ﺒﺎلInstance ﻓﺈﻥ ﺍلOracle ﻴﻘﻭﻡ ﺒﺈﻨﺸﺎﺀ Server Process ﻤﻬﻤﺘﻪ ﺨﺩﻤﺔ ﻁﻠﺒﺎﺕ ﺫﻟﻙ ﺍﻟﻤﺴﺘﺨﺩﻡ ﻭﻴﻅل ﻫﺫﺍ ﺍلProcess Server

ﻤﻭﺠﻭﺩ ﻤﺎﺩﺍﻡ ﺍلSession ﻤﻔﺘﻭﺤﺔ، ﻭﻴﺴﺘﻁﻴﻊ ﺍﻻﻭﺭﻜل ﺇﻨﺸﺎﺀ Server Process ﻟﻜل User Process ﻴﻁﻠﺏ ﺍﻻﺘﺼﺎل ﺒﺎلInstance، ﻭﻫﺫﺍ ﻤﺎ ﻴﺴﻤﻰ ﺒﺎلDedicated Server .

ﻭﺍﻻﻭﺭﻜل ﻟﻴﺱ ﻟﺩﻴﻪ ﻤﺸﻜﻠﺔ ﻓﻲ ﺇﻨﺸﺎﺀ ﺍﻜﺒﺭ ﻋﺩﺩ ﻤﻥ ﺍلServer Processes ﻟﺨﺩﻤﺔ ﺍلUser Processes ﺒﺤﻴﺙ ﻴﻜﻭﻥ User Process ﻟﻜل Server Process ،

ﻠﻜﻥ ﺒﺎﻟﻁﺒﻊ ﻗﺩ ﻴﻜﻭﻥ ﻫﻨﺎﻙ ﺤﺩﻭﺩ ﻟﺴﺭﻋﺔ ﺍل Server Processes ﺍﻟﺘﻲ ﻴﻤﻜﻥ ﺃﻥ ﺘﻌﻤل ﻓﻲ ﻨﻔﺱ ﺍﻟﻠﺤﻅﺔ. ﻭﻴﻤﻜﻥ ﺍﻟﻘﻭل ﺃﻨﻪ ﻜﻠﻤﺎ ﻁﻠﺏ ﻤﺴﺘﺨﺩﻡ ﺍﻻﺘﺼﺎل ﺒﺎلInstance

ﻓﺈﻥ ﺍﻟﻤﺴﺘﻤﻊ Listener ﻴﻘﻭﻡ ﺒﺈﻨﺸﺎﺀ Server Process، ﺃﻤﺎ ﺇﺫﺍ ﻜﺜﺭ ﻋﺩﺩ ﺍلServer process ﻓﺈﻥ ﺍﻟﻤﺴﺘﻤﻊ ﻴﺠﻌل ﻟﻬﻡ ﺼﻔﺎﹰ، ﻋﻤﻭﻤﹰﺎ ﻴﻤﻜﻥ ﺘﻔﺎﺩﻯ ﻫﺫﻩ ﺍﻟﻤﺸﻜﻠﺔ ﺒﺈﻨﺸﺎﺀ

ﻤﺴﺘﻤﻊ ﺁﺨﺭ Listener ﻴﻌﻤل ﻋﻠﻰ ﺒﻭﺭﺕ (Port) ﺁﺨﺭ ﻟﺘﻭﺯﻴﻊ ﺍﻟﻌﻤل ﺒﻴﻨﻬﻡ.

لكن ﻟﻴﺴﺕ ﺍﻟﻤﺸﻜﻠﺔ ﻓﻲ ﺍﻻﻭﺭﻜل ﻭﺤﺩﻩ ﻓﻨﻅﺎﻡ ﺍﻟﺘﺸﻐﻴل ﺍﻟﺘﻲ ﺘﻌﻤل ﻋﻠﻴﻪ ﻗﺎﻋﺩﺓ ﺍﻟﺒﻴﺎﻨﺎﺕ ﻭﻜﺫﻟﻙ ﺍﻟﻤﺨﺩﻡ ﺍﻟﺫﻱ ﺘﻌﻤل ﻋﻠﻴﻪ ﻗﺎﻋﺩﺓ ﺍﻟﺒﻴﺎﻨﺎﺕ؛ ﻜل ﺫﻟﻙ ﻴﺠﻌل ﻟﻙ ﺤﺩﻭﺩ ﻓﻲ

ﺍﻟﺘﻌﺎﻤل ﻤﻊ ﻋﺩﺩ ﻜﺒﻴﺭ ﻤﻥ ﺍلServer Process ﻓﻨﻅﺎﻡ ﺍﻟﺘﺸﻐﻴل ﻭﺤﺠﻡ ﺍﻟﺫﺍﻜﺭﺓ ﻭﺴﺭﻋﺔ ﺍﻟﻤﻌﺎﻟﺞ ﻭﻏﻴﺭﻫﺎ ﻤﻥ ﺍﻟﻤﺅﺜﺭﺍﺕ ﺍﻟﺘﻲ ﺘﺤﺩ ﻤﻥ ﺇﻤﻜﺎﻨﻴﺔ ﻋﺩﺩ ﻻ ﻤﻨﺘﺎﻫﻰ ﻤﻥ ﺍلProcess Server

ﺠﻌﻠﺕ ﺸﺭﻜﺔ ﺍﻭﺭﻜل ﺘﻔﻜﺭ ﻓﻲ ﻤﻭﻀﻭﻉ ﺍلShared Server ﻭﻫﻭ ﺒﺎﺨﺘﺼﺎﺭ ﺇﻨﺸﺎﺀ Shared server ﻟﺨﺩﻤﺔ ﻤﺠﻤﻭﻋﺔ ﻤﻥ ﺍلProcess User ﺒﺩل ﻤﻥ ﺇﻨﺸﺎﺀ Process Server ﻟﻜل

User Process ﻤﻤﺎ ﺠﻌل ﻓﻲ ﻫﺫﺍ ﺍﻟﻨﻤﻁ ﻤﺠﻤﻭﻋﺔ ﻤﻥ ﺍﻟﻔﻭﺍﺌﺩ:

1- ﺘﻘﻠﻴل ﻋﺩﺩ ﺍلServer Process ﺍﻟﻤﺘﺼﻠﺔ ﺒﺎل.Instance.

2- ﺯﻴﺎﺩﺓ ﻋﺩﺩ ﺍﻟﻤﺴﺘﺨﺩﻤﻴﻥ ﺍﻟﻤﺘﺼﻠﻴﻥ ﺒﻘﺎﻋﺩﺓ ﺍﻟﺒﻴﺎﻨﺎﺕ ﺇﺫ ﻻ ﻴﺘﻡ ﺇﻨﺸﺎﺀ Server Process ﻟﻜل ﻤﺴﺘﺨﺩﻡ.

3- ﺘﻘﻠﻴل ﻋﺩﺩ ﺍلServer processes ﺍﻟﻌﺎﻁﻠﺔ ﻋﻥ ﺍﻟﻌﻤل.

4- ﺘﻘﻠﻴل ﺤﺠﻡ ﺍﻟﺫﺍﻜﺭﺓ ﺍﻟﻤﺴﺘﺨﺩﻤﺔ ﻓﻲ ﺍﻟﻌﻤل ﻭﻜﺫﻟﻙ ﺍﻟﻤﻭﺍﺭﺩ ﺍﻷﺨﺭﻯ.

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