I loaded our Veritas bkupexec software on the system and our system performance was dramatically effected, when it ran we started taking 60% CPU performance hits. I ran a top and kswapd seemed to be the culprit. I ran a "sysctl -a | grep kswapd" and it showed: vm.kswapd = 512 32 8, I adjusted the parameters to "512 32 16" and throughput has not improved.
I ran a vmstat over night and noticed that memory seemed to drift down to a low water mark and when the backup agent kicked in kswapd went crazy trying to free memory. We have 16 gigabytes of memory on these systems.
I also noticed the more and more memory being cached. Can someone tell me how to tune this? Do I need to go to the latest kernel, I only wanted to do this as a last resort.


procs memory swap io system cpu
2 r b w swpd free buff cache si so bi bo in cs us sy id
3 0 0 1 0 15385892 72988 332564 0 0 5 7 137 72 0 0 99
4 0 0 1 0 15384356 73224 332568 0 0 2 52 802 273 1 1 99
5 0 0 1 0 15384028 73464 332568 0 0 2 52 637 251 1 1 99
6 0 0 1 0 15383232 73736 332568 0 0 3 52 788 280 1 1 98
8 0 0 1 0 15381284 74252 332568 0 0 2 54 758 271 1 1 98
9 0 0 1 0 15382556 74472 332568 0 0 3 53 382 367 1 1 99
10 0 0 1 0 15382332 74696 332568 0 0 2 52 305 332 1 1 99
11 0 0 1 0 15381172 74936 332568 0 0 3 52 347 388 1 1 99
12 0 0 1 0 15381520 75176 332568 0 0 3 54 291 295 1 1 99
13 0 0 1 0 15381420 75436 332572 0 0 2 55 354 356 1 1 98
14 0 0 1 0 15382056 75676 332572 0 0 2 52 327 365 1 1 99
15 0 0 1 0 15382620 75912 332572 0 0 3 52 372 421 1 1 99
16 1 0 2 0 15383412 76144 332572 0 0 2 57 350 374 0 1 99
17 0 0 1 0 15381324 76380 332572 0 0 2 55 325 334 1 1 99
18 0 1 1 0 15380304

2255 procs memory swap io system cpu
2256 r b w swpd free buff cache si so bi bo in cs us sy id
2257 0 0 2 0 6633180 70728 8624568 0 0 3 61 163 183 1 7 92
2258 0 0 3 0 6632752 71236 8624568 0 0 4 53 166 258 1 23 76
2259 0 0 1 0 6590224 66964 8671268 0 0 791 57 292 566 2 20 77
2260 0 0 1 0 6581992 67300 8679180 0 0 151 56 188 227 1 2 97
2261 1 0 1 0 6570984 67752 8685328 0 0 105 59 196 222 8 18 73
2262 1 0 1 0 6570392 68164 8685452 0 0 5 62 189 178 5 10 85
2263 1 0 1 0 6570024 68556 8685452 0 0 3 58 164 176 8 18 73
2264 0 0 1 0 6574232 68908 8685456 0 0 2 56 164 172 1 3 95
2265 1 0 1 0 6569332 69228 8685456 0 0 2 55 182 164 1 2 97
2266 1 0 1 0 6569052 69644 8685460 0 0 3 57 163 172 8 18 73
2267 0 0 1 0 6573104 70036 8685468 0 0 2 59 166 171 3 6 92
2268 0 0 1 0 6580716 70348 8677600 0 0 2 57 161 168 1 1 98
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