View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0018818 | MMW 5 | DB / Backup | public | 2022-02-07 13:06 | 2022-04-24 20:47 |
| Reporter | Ludek | Assigned To | |||
| Priority | urgent | Severity | minor | Reproducibility | have not tried |
| Status | closed | Resolution | fixed | ||
| Product Version | 5.0 | ||||
| Target Version | 5.0.3 | Fixed in Version | 5.0.3 | ||
| Summary | 0018818: Add SQLite's INI switch for paging to memory | ||||
| Description | In previous MM4 versions we used this SQLite's config: PRAGMA temp_store = MEMORY; which forces all the DB to be paged to RAM, but with this paged to memory e.g. VACUUM fails ( see 0016432 ) with "out of memory" exception on large databases (7 GB, 2.2 million of tracks). We disabled this PRAGMA in MM5 with a note that there should not be a negative impact on performance (just where the pages are written with default page size 2048000 bytes), but we haven't tested DB on a NAS. In the ticket # 3615 it was found that having MM5.DB stored in a NAS location is very slow when deleting tracks, most probably because a lot of network traffic is needed when writing/reading DB and it is slower. With this in mind we may want to add INI switch to re-enable paging to memory to reduce the network penalty when DN is stored on NAS. | ||||
| Additional Information | https://www.mediamonkey.com/forum/viewtopic.php?t=101193 | ||||
| Tags | No tags attached. | ||||
| Fixed in build | 2607 | ||||
|
|
Added switch [SYSTEM] SQLitePageToMemory=0; changing it to 1 enables paging to memory (like in MM4). |
|
|
Added the switch in 2607 @Peke please update corresponding docs. |
|
|
Verified switch functionality 2610 @Rusty I have not found any KB article that optimize DB access speed and https://www.mediamonkey.com/support/knowledge-base/mediamonkey-install-config/modifying-the-mediamonkey-db-and-ini-files/ do not cover that case. New KB article needs to be created to explain how and what this switch do in order to improve DB Behavior, but that sudden loss of access to DB can (but unlikely) result in corruption eg. Removing External hdd from PC or permanent loss of WiFi/Wired connection. Test note: Tested on WiFi reconnect or switching from Wired to WiFi and it does not result in corruption, but UI gets frozen for 1-2 seconds till New IP/Connection is confirmed, NOTE: I also tested when MM Portable is started from USB2.0 HDD where large number Randon HDD read/write IOPS is low this switch can increase speed by 30% |
|
|
Based on the comments above, I've updated: https://www.mediamonkey.com/support/knowledge-base/mediamonkey-install-config/mediamonkey-in-a-shared-networked-environment/ |
|
|
Re Verified 2616 Closing |
