Memory Question

[shawn]

Hi, I am sure this is a simple question but I just can’t seem to find any documentation that can tell me exactly what is wrong. The current box I am running my apache 1.3.28 / Mod_perl server is a quad zeon 500 with 3GB of Ram, the server in general doesn’t get all that many hits, around 300,000 a day. Lately I have been seeing “server reached MaxClients setting, consider raising the MaxClients setting” about 6 seconds after I start up apache. Then I added   #memory info <Location /perl-status>         PerlModule Apache::Status         PerlModule B::TerseSize         SetHandler perl-script         PerlHandler Apache::Status         PerlSetVar StatusTerse On         PerlSetVar StatusTerseSize On         PerlSetVar StatusTerseSizeMainSummary On         PerlSetVar StatusDumper On         PerlSetVar StatusPeek On </Location>   and found the average site to be 37MB so I added   PerlFixupHandler Apache::SizeLimit $Apache::SizeLimit::MAX_UNSHARED_SIZE = 50000; $Apache::SizeLimit::CHECK_EVERY_N_REQUESTS = 10;     Which I thought should cap it at 50MB so 3000 / 50 = 60 so I set   MinSpareServers 5 MaxSpareServers 10 StartServers 20 MaxClients 60 MaxRequestsPerChild 5000   Which in my mind should basically use up all 3GB of memory before I see the “server reached MaxClients setting, consider raising the MaxClients setting” but when the MaxClients error appears the memory is hardly being used at all   Cat /proc/meminfo MemTotal:      3116164 kB MemFree:       1929260 kB Buffers:         40656 kB Cached:         127360 kB SwapCached:      11028 kB Active:        1094232 kB Inactive:        49228 kB HighTotal:     2228208 kB HighFree:      1133632 kB LowTotal:       887956 kB LowFree:        795628 kB SwapTotal:     1048536 kB SwapFree:      1031008 kB Dirty:             340 kB Writeback:           0 kB Mapped:         974096 kB Slab:            29068 kB Committed_AS:  1390760 kB PageTables:       3156 kB VmallocTotal:   114680 kB VmallocUsed:       648 kB VmallocChunk:   114032 kB HugePages_Total:     0 HugePages_Free:      0 Hugepagesize:     4096 kB   Free –lm –s 3                         total       used       free     shared    buffers     cached Mem:                3043       1126       1916          0         39        124 Low:                 867         90        777          0          0          0 High:                 2175       1036       1139          0          0          0 -/+ buffers/cache:           961       2081 Swap:               1023         17       1006   Which I can’t understand….. Why is there free memory if the max clients has already been reached? Shouldn’t there be 3GB used or cached before it wants more? Consequently the server is very up and down…… If anyone could explain this to me I would greatly appreciate it.   Thanks Shawn