what's the default? you probably don't need to change it from the default at all, which should have a good spread. default is 1.25 I think.
On Thu, 12 Nov 2020, Tony Wu wrote: > Hi, > > The engine version we have running right now is 1.5.16. I just saw an > announcement that 1.6.6 is available, so we’ll probably plan to migrate. > > Adjusting growth factor makes sense. I did a quick google and don’t see > any definitive formula to calculate an appropriate number. I’ll probably > start with 2 or 3 and adjust it from there. > > Thanks, > > Tony Wu > > > On Nov 12, 2020, at 3:50 PM, dormando <dorma...@rydia.net> wrote: > > > > 1.5.what? > > > > also yes, chunk_size_growth_factor. don't set it to 1.02. set it to > > something so your slab classes are more evenly distributed. the max is 63. > > > > On Thu, 12 Nov 2020, Tony Wu wrote: > > > >> Hi Dormando, > >> > >> Thanks for the reply, I believe the engine version is 1.5. By multiplier > >> I assumed you meant “chunk_size_growth_factor”, which is currently set > >> at 1.02. > >> > >> Best, > >> > >> Tony Wu > >> > >>> On Nov 12, 2020, at 2:26 PM, dormando <dorma...@rydia.net> wrote: > >>> > >>> What version are they running now? That stat output looks pretty sparse. > >>> > >>> Unfortunately when it comes to elasticache the answer is probably to just > >>> beg them to upgrade to a newer version. they tend to run really old and > >>> newer verisons do a lot better at balancing memory. > >>> > >>> This is also suspect: > >>>> STAT 62:chunk_size 712 > >>>> STAT 62:total_chunks 4416 > >>>> STAT 62:free_chunks 631 > >>>> STAT 62:free_chunks_end 0 > >>>> STAT 63:chunk_size 524288 > >>> > >>> anything you store that's larger than 712 bytes will use half a megabyte > >>> of memory. If you're setting the slab multiplier (-f) to something really > >>> aggressive, you should stop that :) > >>> > >>> On Thu, 12 Nov 2020, Tony Wu wrote: > >>> > >>>> We are currently using memcached provided by AWS ElastiCache service in > >>>> modern mode to store web session keys > >>>> among other things. We are observing session keys being evicted before > >>>> TTL even though the cluster seems to have > >>>> ample free memory, which hints at slab imbalance. I've included a print > >>>> out of slab stats below in terms of > >>>> sizing and total / free pages. > >>>> What would be the best way to smooth out this imbalance? We already > >>>> enabled slab reassign / auto-move under > >>>> modern mode. > >>>> > >>>> Thanks. > >>>> > >>>> STAT 1:chunk_size 96 > >>>> STAT 1:total_chunks 131064 > >>>> STAT 1:free_chunks 1664 > >>>> STAT 1:free_chunks_end 0 > >>>> STAT 2:chunk_size 104 > >>>> STAT 2:total_chunks 60492 > >>>> STAT 2:free_chunks 5327 > >>>> STAT 2:free_chunks_end 0 > >>>> STAT 3:chunk_size 112 > >>>> STAT 3:total_chunks 46810 > >>>> STAT 3:free_chunks 79 > >>>> STAT 3:free_chunks_end 0 > >>>> STAT 4:chunk_size 120 > >>>> STAT 4:total_chunks 26214 > >>>> STAT 4:free_chunks 48 > >>>> STAT 4:free_chunks_end 0 > >>>> STAT 5:chunk_size 128 > >>>> STAT 5:total_chunks 32768 > >>>> STAT 5:free_chunks 6193 > >>>> STAT 5:free_chunks_end 0 > >>>> STAT 6:chunk_size 136 > >>>> STAT 6:total_chunks 23130 > >>>> STAT 6:free_chunks 4594 > >>>> STAT 6:free_chunks_end 0 > >>>> STAT 7:chunk_size 144 > >>>> STAT 7:total_chunks 7281 > >>>> STAT 7:free_chunks 5894 > >>>> STAT 7:free_chunks_end 0 > >>>> STAT 8:chunk_size 152 > >>>> STAT 8:total_chunks 13796 > >>>> STAT 8:free_chunks 12008 > >>>> STAT 8:free_chunks_end 0 > >>>> STAT 9:chunk_size 160 > >>>> STAT 9:total_chunks 6553 > >>>> STAT 9:free_chunks 6316 > >>>> STAT 9:free_chunks_end 0 > >>>> STAT 10:chunk_size 168 > >>>> STAT 10:total_chunks 6241 > >>>> STAT 10:free_chunks 6186 > >>>> STAT 10:free_chunks_end 0 > >>>> STAT 11:chunk_size 176 > >>>> STAT 11:total_chunks 5957 > >>>> STAT 11:free_chunks 5946 > >>>> STAT 11:free_chunks_end 0 > >>>> STAT 12:chunk_size 184 > >>>> STAT 12:total_chunks 5698 > >>>> STAT 12:free_chunks 5664 > >>>> STAT 12:free_chunks_end 0 > >>>> STAT 13:chunk_size 192 > >>>> STAT 13:total_chunks 5461 > >>>> STAT 13:free_chunks 5380 > >>>> STAT 13:free_chunks_end 0 > >>>> STAT 14:chunk_size 200 > >>>> STAT 14:total_chunks 5242 > >>>> STAT 14:free_chunks 5135 > >>>> STAT 14:free_chunks_end 0 > >>>> STAT 15:chunk_size 208 > >>>> STAT 15:total_chunks 5041 > >>>> STAT 15:free_chunks 4892 > >>>> STAT 15:free_chunks_end 0 > >>>> STAT 16:chunk_size 216 > >>>> STAT 16:total_chunks 4854 > >>>> STAT 16:free_chunks 4770 > >>>> STAT 16:free_chunks_end 0 > >>>> STAT 17:chunk_size 224 > >>>> STAT 17:total_chunks 4681 > >>>> STAT 17:free_chunks 4655 > >>>> STAT 17:free_chunks_end 0 > >>>> STAT 18:chunk_size 232 > >>>> STAT 18:total_chunks 4519 > >>>> STAT 18:free_chunks 4489 > >>>> STAT 18:free_chunks_end 0 > >>>> STAT 19:chunk_size 240 > >>>> STAT 19:total_chunks 4369 > >>>> STAT 19:free_chunks 4345 > >>>> STAT 19:free_chunks_end 0 > >>>> STAT 20:chunk_size 248 > >>>> STAT 20:total_chunks 4228 > >>>> STAT 20:free_chunks 4217 > >>>> STAT 20:free_chunks_end 0 > >>>> STAT 21:chunk_size 256 > >>>> STAT 21:total_chunks 4096 > >>>> STAT 21:free_chunks 4091 > >>>> STAT 21:free_chunks_end 0 > >>>> STAT 22:chunk_size 264 > >>>> STAT 22:total_chunks 3971 > >>>> STAT 22:free_chunks 3966 > >>>> STAT 22:free_chunks_end 0 > >>>> STAT 23:chunk_size 272 > >>>> STAT 23:total_chunks 3855 > >>>> STAT 23:free_chunks 3851 > >>>> STAT 23:free_chunks_end 0 > >>>> STAT 24:chunk_size 280 > >>>> STAT 24:total_chunks 3744 > >>>> STAT 24:free_chunks 3738 > >>>> STAT 24:free_chunks_end 0 > >>>> STAT 25:chunk_size 288 > >>>> STAT 25:total_chunks 3640 > >>>> STAT 25:free_chunks 3638 > >>>> STAT 25:free_chunks_end 0 > >>>> STAT 26:chunk_size 296 > >>>> STAT 26:total_chunks 3542 > >>>> STAT 26:free_chunks 3533 > >>>> STAT 26:free_chunks_end 0 > >>>> STAT 27:chunk_size 304 > >>>> STAT 27:total_chunks 3449 > >>>> STAT 27:free_chunks 3448 > >>>> STAT 27:free_chunks_end 0 > >>>> STAT 28:chunk_size 312 > >>>> STAT 28:total_chunks 3360 > >>>> STAT 28:free_chunks 3350 > >>>> STAT 28:free_chunks_end 0 > >>>> STAT 29:chunk_size 320 > >>>> STAT 29:total_chunks 3276 > >>>> STAT 29:free_chunks 3273 > >>>> STAT 29:free_chunks_end 0 > >>>> STAT 30:chunk_size 328 > >>>> STAT 30:total_chunks 3196 > >>>> STAT 30:free_chunks 3174 > >>>> STAT 30:free_chunks_end 0 > >>>> STAT 31:chunk_size 336 > >>>> STAT 31:total_chunks 3120 > >>>> STAT 31:free_chunks 3118 > >>>> STAT 31:free_chunks_end 0 > >>>> STAT 32:chunk_size 344 > >>>> STAT 32:total_chunks 3048 > >>>> STAT 32:free_chunks 3043 > >>>> STAT 32:free_chunks_end 0 > >>>> STAT 33:chunk_size 352 > >>>> STAT 33:total_chunks 2978 > >>>> STAT 33:free_chunks 2954 > >>>> STAT 33:free_chunks_end 0 > >>>> STAT 34:chunk_size 360 > >>>> STAT 34:total_chunks 2912 > >>>> STAT 34:free_chunks 2903 > >>>> STAT 34:free_chunks_end 0 > >>>> STAT 35:chunk_size 368 > >>>> STAT 35:total_chunks 2849 > >>>> STAT 35:free_chunks 2828 > >>>> STAT 35:free_chunks_end 0 > >>>> STAT 36:chunk_size 376 > >>>> STAT 36:total_chunks 2788 > >>>> STAT 36:free_chunks 2766 > >>>> STAT 36:free_chunks_end 0 > >>>> STAT 37:chunk_size 384 > >>>> STAT 37:total_chunks 2730 > >>>> STAT 37:free_chunks 2684 > >>>> STAT 37:free_chunks_end 0 > >>>> STAT 38:chunk_size 392 > >>>> STAT 38:total_chunks 2674 > >>>> STAT 38:free_chunks 2621 > >>>> STAT 38:free_chunks_end 0 > >>>> STAT 39:chunk_size 400 > >>>> STAT 39:total_chunks 2621 > >>>> STAT 39:free_chunks 2564 > >>>> STAT 39:free_chunks_end 0 > >>>> STAT 40:chunk_size 408 > >>>> STAT 40:total_chunks 2570 > >>>> STAT 40:free_chunks 2527 > >>>> STAT 40:free_chunks_end 0 > >>>> STAT 41:chunk_size 416 > >>>> STAT 41:total_chunks 2520 > >>>> STAT 41:free_chunks 2216 > >>>> STAT 41:free_chunks_end 0 > >>>> STAT 42:chunk_size 424 > >>>> STAT 42:total_chunks 2473 > >>>> STAT 42:free_chunks 2256 > >>>> STAT 42:free_chunks_end 0 > >>>> STAT 43:chunk_size 432 > >>>> STAT 43:total_chunks 2427 > >>>> STAT 43:free_chunks 2299 > >>>> STAT 43:free_chunks_end 0 > >>>> STAT 44:chunk_size 440 > >>>> STAT 44:total_chunks 2383 > >>>> STAT 44:free_chunks 1898 > >>>> STAT 44:free_chunks_end 0 > >>>> STAT 45:chunk_size 448 > >>>> STAT 45:total_chunks 2340 > >>>> STAT 45:free_chunks 1962 > >>>> STAT 45:free_chunks_end 0 > >>>> STAT 46:chunk_size 456 > >>>> STAT 46:total_chunks 2299 > >>>> STAT 46:free_chunks 2192 > >>>> STAT 46:free_chunks_end 0 > >>>> STAT 47:chunk_size 472 > >>>> STAT 47:total_chunks 2221 > >>>> STAT 47:free_chunks 2061 > >>>> STAT 47:free_chunks_end 0 > >>>> STAT 48:chunk_size 488 > >>>> STAT 48:total_chunks 2148 > >>>> STAT 48:free_chunks 2047 > >>>> STAT 48:free_chunks_end 0 > >>>> STAT 49:chunk_size 504 > >>>> STAT 49:total_chunks 2080 > >>>> STAT 49:free_chunks 1955 > >>>> STAT 49:free_chunks_end 0 > >>>> STAT 50:chunk_size 520 > >>>> STAT 50:total_chunks 2016 > >>>> STAT 50:free_chunks 1788 > >>>> STAT 50:free_chunks_end 0 > >>>> STAT 51:chunk_size 536 > >>>> STAT 51:total_chunks 1956 > >>>> STAT 51:free_chunks 1870 > >>>> STAT 51:free_chunks_end 0 > >>>> STAT 52:chunk_size 552 > >>>> STAT 52:total_chunks 1899 > >>>> STAT 52:free_chunks 1829 > >>>> STAT 52:free_chunks_end 0 > >>>> STAT 53:chunk_size 568 > >>>> STAT 53:total_chunks 1846 > >>>> STAT 53:free_chunks 1762 > >>>> STAT 53:free_chunks_end 0 > >>>> STAT 54:chunk_size 584 > >>>> STAT 54:total_chunks 1795 > >>>> STAT 54:free_chunks 1613 > >>>> STAT 54:free_chunks_end 0 > >>>> STAT 55:chunk_size 600 > >>>> STAT 55:total_chunks 1747 > >>>> STAT 55:free_chunks 1446 > >>>> STAT 55:free_chunks_end 0 > >>>> STAT 56:chunk_size 616 > >>>> STAT 56:total_chunks 1702 > >>>> STAT 56:free_chunks 1358 > >>>> STAT 56:free_chunks_end 0 > >>>> STAT 57:chunk_size 632 > >>>> STAT 57:total_chunks 1659 > >>>> STAT 57:free_chunks 1497 > >>>> STAT 57:free_chunks_end 0 > >>>> STAT 58:chunk_size 648 > >>>> STAT 58:total_chunks 1618 > >>>> STAT 58:free_chunks 1398 > >>>> STAT 58:free_chunks_end 0 > >>>> STAT 59:chunk_size 664 > >>>> STAT 59:total_chunks 3158 > >>>> STAT 59:free_chunks 1784 > >>>> STAT 59:free_chunks_end 0 > >>>> STAT 60:chunk_size 680 > >>>> STAT 60:total_chunks 1542 > >>>> STAT 60:free_chunks 1301 > >>>> STAT 60:free_chunks_end 0 > >>>> STAT 61:chunk_size 696 > >>>> STAT 61:total_chunks 3012 > >>>> STAT 61:free_chunks 302 > >>>> STAT 61:free_chunks_end 0 > >>>> STAT 62:chunk_size 712 > >>>> STAT 62:total_chunks 4416 > >>>> STAT 62:free_chunks 631 > >>>> STAT 62:free_chunks_end 0 > >>>> STAT 63:chunk_size 524288 > >>>> STAT 63:total_chunks 26108 > >>>> STAT 63:free_chunks 0 > >>>> STAT 63:free_chunks_end 0 > >>>> > >>>> -- > >>>> > >>>> --- > >>>> You received this message because you are subscribed to the Google > >>>> Groups "memcached" group. > >>>> To unsubscribe from this group and stop receiving emails from it, send > >>>> an email to > >>>> memcached+unsubscr...@googlegroups.com. > >>>> To view this discussion on the web visit > >>>> https://groups.google.com/d/msgid/memcached/927615f7-187d-4c8f-9e08-f1f341b9a04an%40googlegroups.com. > >>>> > >>>> > >>> > >>> -- > >>> > >>> --- > >>> You received this message because you are subscribed to the Google Groups > >>> "memcached" group. > >>> To unsubscribe from this group and stop receiving emails from it, send an > >>> email to memcached+unsubscr...@googlegroups.com. > >>> To view this discussion on the web visit > >>> https://groups.google.com/d/msgid/memcached/alpine.DEB.2.22.394.2011121424300.2800104%40dskull. > >> > >> -- > >> > >> --- > >> You received this message because you are subscribed to the Google Groups > >> "memcached" group. > >> To unsubscribe from this group and stop receiving emails from it, send an > >> email to memcached+unsubscr...@googlegroups.com. > >> To view this discussion on the web visit > >> https://groups.google.com/d/msgid/memcached/76D01DF5-D89D-4CF1-B786-3F1B8FA9B2A0%40gmail.com. > >> > > > > -- > > > > --- > > You received this message because you are subscribed to the Google Groups > > "memcached" group. > > To unsubscribe from this group and stop receiving emails from it, send an > > email to memcached+unsubscr...@googlegroups.com. > > To view this discussion on the web visit > > https://groups.google.com/d/msgid/memcached/alpine.DEB.2.22.394.2011121549540.2800104%40dskull. > > -- > > --- > You received this message because you are subscribed to the Google Groups 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