On Fri, 18 Feb 2000, Karl Swartz wrote:
to the cluster partner.) Data and metadata writes are logged to the first chunk until one of two events triggers the establishment of a new consistency point on disk, which consists of writing out all of the logged writes while sending new writes to the other NVRAM chunk.
Is it really both data and metadata that gets written to NVRAM? What gets put into the RAM cache, then, just disk reads? Where to the WAFL logs get written?
I was just examining one of my F740's, which is often running 4-5,000 ops/s with 0 or 1 minute cache ages, but the NVRAM stats don't seem as bad as that dude with the F760:
cp_from_timer = 153482 cp_from_snapshot = 94030 cp_from_low_water = 0 cp_from_high_water = 0 cp_from_log_full = 50913 cp_from_timer_nvlog = 0 cp_from_cp = 347
~20% are "log full" writes, higher than Bruce's rule-of-thumb 10%, but the nasty one people are mentioning "cp_from_cp" is pretty small.
Today is a medium load day:
CPU NFS CIFS HTTP Net kB/s Disk kB/s Tape kB/s Cache in out read write read write age 82% 1601 3400 0 941 5579 2195 0 0 0 1 85% 1350 3779 0 1198 4413 2343 0 0 0 1 87% 1641 2984 0 1183 4892 3094 377 0 0 1 94% 1275 3082 0 805 5252 2995 3041 0 0 1 92% 1958 3191 0 1141 6778 3735 0 0 0 1 89% 1196 3273 0 2236 4657 3617 0 0 0 1 91% 978 3482 0 2105 6173 2707 0 0 0 1 90% 1405 3746 0 1249 5568 2004 0 0 0 1 94% 802 3730 0 971 3304 3325 1160 0 0 1 97% 1081 3274 0 930 6537 3479 4832 0 0 1 89% 1210 3642 0 2411 5467 2417 0 0 0 1 89% 1324 3333 0 1577 4586 1934 0 0 0 1 91% 1260 3346 0 2342 3744 2036 0 0 0 1 89% 1632 2997 0 1120 4948 1662 0 0 0 1 83% 1358 2681 0 1206 5477 1988 0 0 0 1 82% 694 2300 0 602 1921 4930 5164 0 0 1 94% 1179 3836 0 3925 5718 2449 874 0 0 1 79% 1023 2750 0 1829 6107 3249 0 0 0 1
Having more options regarding NVRAM and RAM cache configurations in filers would be great, not this current "one-size-fits-all" sh^H^Hstuff.
Until next time...
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