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Lot of LWPs in vmstat. What it means? How to fix?

User_Y2Y3IJul 7 2020 — edited Jul 19 2020

Hello,

I have Solaris 11.2 Sparc server, which is a Oracle DB server. Since some time I have been informed latency and slowness on the database side. I ran memstat command and it shows me Kernel is taking more than 50% and free memory is very less. I understand that ZFS arc memory could have been set, but that would impact ZFS file data (I guess).

vmstat shows me swap out lot of LWPS in w fileld. Probably doesn't looks ideal.

My questions are -

- Is it memory, I would increase or swap ?

- When kernel is showing 55% of total memory, is it DB/app which is consuming this much? DB guys are blaming on us (Admin guys) that your server/OS is having not-ideal setup, our database is not supposed to consume so much. I have doubts about it.

root@oradb-prod24:~# echo ::memstat | mdb -k

Page Summary Pages Bytes %Tot

----------------- ---------------- ---------------- ----

Kernel 2292714 17.4G 55%

Guest 0 0 0%

ZFS Metadata 13953 109.0M 0%

ZFS File Data 4500 35.1M 0%

Anon 1804250 13.7G 43%

Exec and libs 28421 222.0M 1%

Page cache 11723 91.5M 0%

Free (cachelist) 46 368k 0%

Free (freelist) 38697 302.3M 1%

Total 4194304 32G

root@oradb-prod24:~#

root@oradb-prod24:~# vmstat 1 5 kthr memory page disk faults cpu

r b w swap free re mf pi po fr de sr vc vc vc vc in sy cs us sy id

0 0 41 29721768 871728 132 695 1 1 1 514488 9 19 19 47 10 10573 600322 14357 5 3 92

0 0 442 23559016 436608 340 900 0 0 0 514488 0 107 20 516 7 23337 13005 41205 3 3 94

0 0 442 23559016 437720 0 91 0 0 0 463040 0 33 10 512 8 22148 20037 38870 3 3 94

0 0 442 23559016 436856 134 347 0 72 72 514488 0 5 20 536 5 21031 38934 37366 3 8 89

0 0 442 23559016 436728 0 64 0 88 88 463040 0 172 25 604 9 6867 10689 7761 2 2 95

root@oradb-prod24:~#

Please suggest me, if this data is telling something.

Thanks

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Added on Jul 7 2020
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