Indexing Mail faster

[Peter Hodur]

> * Kevin Laurie <superinterstellar at gmail.com> 2015.01.24 19:41:
>
> > Currently the time it takes to search 25,000mails is 4mins. If indexed
> how
> > much faster are we looking at?
>
> With a current version of Dovecot a search is pretty fast _without_ using
> external indexes. I have a view defined (virtual plugin) with around 22.000
> messages in it, and searching the full view only takes 2.5 seconds:
>
>
hmmm, could you please tell me more about your setup? What storage format
do you use? Maildir or? What is the cumulative size of your messages?

My results without FTS on ZFS FS with SSD L2ARC are not so good:

a4 select INBOX._OLD-OUTLOOK
* FLAGS (\Answered \Flagged \Deleted \Seen \Draft $Junk $NotJunk
JunkRecorded $Forwarded)
* OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft $Junk
$NotJunk JunkRecorded $Forwarded \*)] Flags permitted.
** 7748 EXISTS*
* 0 RECENT
* OK [UIDVALIDITY 1421198037] UIDs valid
* OK [UIDNEXT 11509] Predicted next UID
* OK [HIGHESTMODSEQ 12204] Highest
a4 OK [READ-WRITE] Select completed (0.001 secs).

a5 search charset utf-8 body "mall"
* SEARCH 2 49 101 117 158 171 185 192 197 202 207 223 228 234 236 240 249
279 280 281 287 288 289 290 297 321 327 337 344 351 360 370 373 385 389 390
391 398 405 413 424 444 458 463 470 474 480 482 505 513 520 530 531 532 533
543 559 560 561 562 563 566 588 593 597 625 630 639 644 656 671 672 677 692
720 723 734 738 741 745 752 755 757 765 775 777 784 791 818 820 821 833 855
863 864 868 881 896 910 917 922 926 928 931 991 996 997 998 1000 1010 1011
1012 1014 1018 1019 1026 1047 1068 1077 1095 1101 1105 1122 1136 1137 1140
1155 1160 1166 1171 1179 1180 1197 1208 1229 1239 1258 1263 1271 1282 1286
1290 1298 1319 1364 1365 1370 1386 1408 1410 1429 1463 1465 1470 1471 1494
1518 1522 1529 1530 1536 1541 1548 1571 1581 1585 1588 1594 1605 1606 1611
1612 1619 1620 1625 1652 1666 1667 1729 1730 1731 1732 1733 1734 1735 1781
1782 1817 1818 1897 1900 1921 1940 1946 1960 1972 1981 1995 1998 2002 2006
2028 2049 2057 2095 2100 2157 2168 2181 2185 2192 2203 2204 2207 2208 2210
2220 2225 2255 2273 2282 2283 2288 2289 2317 2320 2340 2367 2374 2377 2378
2379 2384 2389 2402 2409 2436 2459 2475 2476 2488 2504 2519 2538 2539 2551
2566 2572 2597 2599 2603 2617 2629 2664 2698 2716 2731 2733 2753 2754 2780
2805 2808 2815 2818 2850 2861 2862 2867 2886 2896 2900 2914 2931 2936 2938
2939 2950 2969 2990 3017 3019 3062 3075 3094 3101 3115 3138 3159 3161 3178
3185 3190 3204 3217 3218 3248 3263 3265 3266 3273 3282 3288 3295 3386 3428
3453 3476 3478 3479 3511 3548 3606 3629 3693 3694 3737 3793 3799 3801 3808
3812 3814 3815 3834 3849 3860 3862 3880 3910 3917 3930 3932 3952 3953 3954
3957 3959 3968 3971 3973 3978 3979 3980 4008 4022 4040 4057 4058 4059 4063
4064 4066 4069 4070 4075 4096 4112 4131 4132 4133 4141 4143 4144 4145 4146
4147 4167 4174 4199 4201 4202 4203 4206 4211 4217 4218 4226 4229 4258 4259
4267 4287 4357 4359 4363 4364 4365 4367 4390 4391 4462 4475 4497 4502 4538
4540 4552 4557 4558 4561 4563 4567 4571 4572 4573 4575 4577 4593 4594 4604
4611 4619 4628 4638 4639 4662 4672 4678 4679 4692 4696 4785 4786 4787 4788
4789 4792 4793 4794 4802 4817 4818 4819 4820 4836 4857 4874 4887 4901 4905
4906 4907 4908 4911 4925 4928 4940 4941 4953 5060 5103 5116 5118 5129 5131
5136 5158 5163 5182 5184 5203 5212 5216 5269 5270 5271 5272 5273 5276 5277
5278 5286 5301 5302 5303 5304 5320 5341 5358 5371 5385 5389 5390 5391 5392
5395 5409 5412 5424 5425 5437 5544 5587 5600 5602 5613 5615 5620 5642 5647
5666 5668 5687 5696 5700 5736 5740 5749 5764 5783 5809 5814 5853 5866 5867
5877 5888 5895 5896 5897 5898 5899 5908 5910 5911 5912 5939 5950 5958 5990
6000 6059 6074 6095 6097 6112 6137 6141 6189 6193 6212 6228 6229 6233 6271
6273 6275 6285 6310 6317 6335 6383 6384 6397 6427 6430 6459 6463 6482 6492
6506 6565 6585 6620 6670 6673 6675 6705 6715 6716 6741 6812 6826 6852 6859
6895 6896 6907 6913 6919 6935 6943 6948 6979 7023 7025 7035 7039 7042 7108
7131 7145 7163 7171 7172 7194 7198 7199 7203 7256 7257 7294 7303 7317 7322
7343 7344 7347 7348 7352 7386 7390 7391 7392 7393 7407 7408 7409 7417 7418
7419 7420 7421 7426 7432 7437 7462 7467 7468 7473 7474 7475 7488 7502 7503
7558 7588 7589 7628 7685 7695 7699 7703 7723
*a5 OK Search completed (7.846 secs).*


Searching against "subject" is pretty fast, few miliseconds ...