(VERY) Slow Query - PostgreSQL 9.2

Hi all,

I'm trying to get the query below a better performance.. but just don't know what else I can do...

Please, have a look and let me know if you can help somehow.. also.. if you need some extra data jet ask me please.

* Note that the gorfs.inode_segments table is 1.7TB size

I have the following Query:

explain analyze
SELECT split_part(full_path, '/', 4)::INT AS account_id,      split_part(full_path, '/', 6)::INT AS note_id,      split_part(full_path, '/', 9)::TEXT AS variation,      st_size,      segment_index,      reverse(split_part(reverse(full_path), '/', 1)) as file_name,      i.st_ino,      full_path,      (i.st_size / 1000000::FLOAT)::NUMERIC(5,2) || 'MB' AS size_mb
FROM gorfs.inodes i
JOIN gorfs.inode_segments s ON i.st_ino = s.st_ino_target
WHERE     i.checksum_md5 IS NOT NULL AND s.full_path ~ '^/userfiles/account/[0-9]+/[a-z]+/[0-9]+' AND i.st_size > 0; split_part(s.full_path, '/', 4)::INT IN (

SELECT account.id       FROM public.ja_clients AS account       WHERE       NOT (               ((account.last_sub_pay > EXTRACT('epoch' FROM (transaction_timestamp() - CAST('4 Months' AS INTERVAL)))) AND (account.price_model > 0)) OR               (account.regdate > EXTRACT('epoch' FROM (transaction_timestamp() - CAST('3 Month' AS INTERVAL)))) OR               (((account.price_model = 0) AND (account.jobcredits > 0)) AND (account.last_login > EXTRACT('epoch' FROM (transaction_timestamp() - CAST('4 Month' AS INTERVAL)))))       ) LIMIT 100
);

• Explain analyze link: http://explain.depesz.com/s/Oc6

The query is taking ages, and I can't get the problem solved.

These are the index I've already created on the inode_segments table:

Indexes:   "ix_account_id_from_full_path" "btree" (("split_part"("full_path"::"text", '/'::"text", 4)::integer)) WHERE "full_path"::"text" ~ '^/userfiles/account/[0-9]+/[a-z]+/[0-9]+'::"text"   "ix_inode_segments_ja_files_lookup" "btree" ((
CASE   WHEN "full_path"::"text" ~ '/[^/]*\.[^/]*$'::"text" THEN "upper"("regexp_replace"("full_path"::"text", '.*\.'::"text", ''::"text", 'g'::"text"))   ELSE NULL::"text"
END)) WHERE "gorfs"."is_kaminski_note_path"("full_path"::"text")   "ix_inode_segments_notes_clientids" "btree" (("split_part"("full_path"::"text", '/'::"text", 4)::integer)) WHERE "gorfs"."is_kaminski_note_path"("full_path"::"text")   "ix_inode_segments_notes_clientids2" "btree" ("full_path")   "ix_inode_segments_notes_fileids" "btree" (("split_part"("full_path"::"text", '/'::"text", 8)::integer)) WHERE "gorfs"."is_kaminski_note_path"("full_path"::"text")   "ix_inode_segments_notes_noteids" "btree" ((NULLIF("split_part"("full_path"::"text", '/'::"text", 6), 'unassigned'::"text")::integer)) WHERE "gorfs"."is_kaminski_note_path"("full_path"::"text")

These are the index I've already created on the inodes table:

 Indexes:   "ix_inodes_checksum_st_size" "btree" ("checksum_md5", "st_size") WHERE "checksum_md5" IS NOT NULL

Question:

What else can I do to improve the Performance of the Query?