cgspace-notes/content/posts/2020-02.md

---
title: "February, 2020"
date: 2020-02-02T11:56:30+02:00
author: "Alan Orth"
categories: ["Notes"]
---

## 2020-02-02

- Continue working on porting CGSpace's DSpace 5 code to DSpace 6.3 that I started yesterday
  - Sign up for an account with MaxMind so I can get the GeoLite2-City.mmdb database
  - I still need to wire up the API credentials and cron job into the Ansible infrastructure playbooks
  - Fix some minor issues in the config and XMLUI themes, like removing Atmire stuff
  - The code finally builds and runs with a fresh install

<!--more-->

  - Now we don't specify the build environment because site modification are in `local.cfg`, so we just build like this:

```
$ schedtool -D -e ionice -c2 -n7 nice -n19 mvn -U -Dmirage2.on=true -Dmirage2.deps.included=false clean package
```

- And it seems that we need to enabled `pg_crypto` now (used for UUIDs):

```
$ psql -h localhost -U postgres dspace63
dspace63=# CREATE EXTENSION pgcrypto;
CREATE EXTENSION pgcrypto;
```

- I tried importing a PostgreSQL snapshot from CGSpace and had errors due to missing Atmire database migrations
  - If I try to run `dspace database migrate` I get the IDs of the migrations that are missing
  - I delete them manually in psql:

```
dspace63=# DELETE FROM schema_version WHERE version IN ('5.0.2015.01.27', '5.6.2015.12.03.2', '5.6.2016.08.08', '5.0.2017.04.28', '5.0.2017.09.25', '5.8.2015.12.03.3');
```

- Then I ran `dspace database migrate` and got an error:

```
$ ~/dspace63/bin/dspace database migrate

Database URL: jdbc:postgresql://localhost:5432/dspace63?ApplicationName=dspaceCli
Migrating database to latest version... (Check dspace logs for details)
Migration exception:
java.sql.SQLException: Flyway migration error occurred
        at org.dspace.storage.rdbms.DatabaseUtils.updateDatabase(DatabaseUtils.java:673)
        at org.dspace.storage.rdbms.DatabaseUtils.updateDatabase(DatabaseUtils.java:576)
        at org.dspace.storage.rdbms.DatabaseUtils.main(DatabaseUtils.java:221)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.dspace.app.launcher.ScriptLauncher.runOneCommand(ScriptLauncher.java:229)
        at org.dspace.app.launcher.ScriptLauncher.main(ScriptLauncher.java:81)
Caused by: org.flywaydb.core.internal.dbsupport.FlywaySqlScriptException:
Migration V6.0_2015.03.07__DS-2701_Hibernate_migration.sql failed
-----------------------------------------------------------------
SQL State  : 2BP01
Error Code : 0
Message    : ERROR: cannot drop table metadatavalue column resource_id because other objects depend on it
  Detail: view eperson_metadata depends on table metadatavalue column resource_id
  Hint: Use DROP ... CASCADE to drop the dependent objects too.
Location   : org/dspace/storage/rdbms/sqlmigration/postgres/V6.0_2015.03.07__DS-2701_Hibernate_migration.sql (/home/aorth/src/git/DSpace-6.3/file:/home/aorth/dspace63/lib/dspace-api-6.3.jar!/org/dspace/storage/rdbms/sqlmigration/postgres/V6.0_2015.03.07__DS-2701_Hibernate_migration.sql)
Line       : 391
Statement  : ALTER TABLE metadatavalue DROP COLUMN IF EXISTS resource_id

        at org.flywaydb.core.internal.dbsupport.SqlScript.execute(SqlScript.java:117)
        at org.flywaydb.core.internal.resolver.sql.SqlMigrationExecutor.execute(SqlMigrationExecutor.java:71)
        at org.flywaydb.core.internal.command.DbMigrate.doMigrate(DbMigrate.java:352)
        at org.flywaydb.core.internal.command.DbMigrate.access$1100(DbMigrate.java:47)
        at org.flywaydb.core.internal.command.DbMigrate$4.doInTransaction(DbMigrate.java:308)
        at org.flywaydb.core.internal.util.jdbc.TransactionTemplate.execute(TransactionTemplate.java:72)
        at org.flywaydb.core.internal.command.DbMigrate.applyMigration(DbMigrate.java:305)
        at org.flywaydb.core.internal.command.DbMigrate.access$1000(DbMigrate.java:47)
        at org.flywaydb.core.internal.command.DbMigrate$2.doInTransaction(DbMigrate.java:230)
        at org.flywaydb.core.internal.command.DbMigrate$2.doInTransaction(DbMigrate.java:173)
        at org.flywaydb.core.internal.util.jdbc.TransactionTemplate.execute(TransactionTemplate.java:72)
        at org.flywaydb.core.internal.command.DbMigrate.migrate(DbMigrate.java:173)
        at org.flywaydb.core.Flyway$1.execute(Flyway.java:959)
        at org.flywaydb.core.Flyway$1.execute(Flyway.java:917)
        at org.flywaydb.core.Flyway.execute(Flyway.java:1373)
        at org.flywaydb.core.Flyway.migrate(Flyway.java:917)
        at org.dspace.storage.rdbms.DatabaseUtils.updateDatabase(DatabaseUtils.java:662)
        ... 8 more
Caused by: org.postgresql.util.PSQLException: ERROR: cannot drop table metadatavalue column resource_id because other objects depend on it
  Detail: view eperson_metadata depends on table metadatavalue column resource_id
  Hint: Use DROP ... CASCADE to drop the dependent objects too.
        at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2422)
        at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2167)
        at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:306)
        at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:441)
        at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:365)
        at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:307)
        at org.postgresql.jdbc.PgStatement.executeCachedSql(PgStatement.java:293)
        at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:270)
        at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:266)
        at org.apache.commons.dbcp2.DelegatingStatement.execute(DelegatingStatement.java:291)
        at org.apache.commons.dbcp2.DelegatingStatement.execute(DelegatingStatement.java:291)
        at org.flywaydb.core.internal.dbsupport.JdbcTemplate.executeStatement(JdbcTemplate.java:238)
        at org.flywaydb.core.internal.dbsupport.SqlScript.execute(SqlScript.java:114)
        ... 24 more
```

- I think I might need to update the sequences first... nope
- Perhaps it's due to some missing bitstream IDs and I need to run `dspace cleanup` on CGSpace and take a new PostgreSQL dump... nope
- A thread on the dspace-tech mailing list regarding this migration noticed that his database had some views created that were using the `resource_id` column
- Our database had the same issue, where the `eperson_metadata` view was created by something (Atmire module?) but has no references in the vanilla DSpace code, so I dropped it and tried the migration again:

```
dspace63=# DROP VIEW eperson_metadata;
DROP VIEW
```

- After that the migration was successful and DSpace starts up successfully and begins indexing
  - xmlui, solr, jspui, rest, and oai are working (rest was redirecting to HTTPS, so I set the Tomcat connector to `secure="true"` and it fixed it on localhost, but caused other issues so I disabled it for now)
  - I started diffing our themes against the Mirage 2 reference theme to capture the latest changes

## 2020-02-03

- Update DSpace mimetype fallback images from [KDE Breeze Icons](https://github.com/KDE/breeze-icons) project
  - Our icons are four years old (see [my bitstream icons demo](https://alanorth.github.io/dspace-bitstream-icons/))
- Issues remaining in the DSpace 6 port of our CGSpace 5.x code:
  - [x] Community and collection pages only show one recent submission (seems that there is only one item in Solr?)
  - [x] Community and collection pages have tons of "Browse" buttons that we need to remove
  - [x] Order of navigation elements in right side bar ("My Account" etc, compare to DSpace Test)
  - [ ] Home page trail says "CGSpace Home" instead of "CGSpace Home / Community List" (see DSpace Test)
- There are lots of errors in the DSpace log, which might explain some of the issues with recent submissions / Solr:

```
2020-02-03 10:27:14,485 ERROR org.dspace.browse.ItemCountDAOSolr @ caught exception: 
org.dspace.discovery.SearchServiceException: Invalid UUID string: 1
2020-02-03 13:20:20,475 ERROR org.dspace.app.xmlui.aspect.discovery.AbstractRecentSubmissionTransformer @ Caught SearchServiceException while retrieving recent submission for: home page
org.dspace.discovery.SearchServiceException: Invalid UUID string: 111210
```

- If I look in Solr's search core I do actually see items with integers for their resource ID, which I think are all supposed to be UUIDs now...
- I dropped all the documents in the search core:

```
$ http --print b 'http://localhost:8080/solr/search/update?stream.body=<delete><query>*:*</query></delete>&commit=true'
```

- Still didn't work, so I'm going to try a clean database import and migration:

```
$ createdb -h localhost -U postgres -O dspacetest --encoding=UNICODE dspace63
$ psql -h localhost -U postgres -c 'alter user dspacetest superuser;'
$ pg_restore -h localhost -U postgres -d dspace63 -O --role=dspacetest -h localhost dspace_2020-01-27.backup
$ psql -h localhost -U postgres -c 'alter user dspacetest nosuperuser;'
$ psql -h localhost -U postgres dspace63                               
dspace63=# CREATE EXTENSION pgcrypto;
dspace63=# DELETE FROM schema_version WHERE version IN ('5.0.2015.01.27', '5.6.2015.12.03.2', '5.6.2016.08.08', '5.0.2017.04.28', '5.0.2017.09.25', '5.8.2015.12.03.3');
dspace63=# DROP VIEW eperson_metadata;
dspace63=# \q
$ psql -h localhost -U postgres -f ~/src/git/DSpace/dspace/etc/postgres/update-sequences.sql dspace63
$ ~/dspace63/bin/dspace database migrate
```

- I notice that the indexing doesn't work correctly if I start it manually with `dspace index-discovery -b` (search.resourceid becomes an integer!)
  - If I induce an indexing by touching `dspace/solr/search/conf/reindex.flag` the search.resourceid are all UUIDs...
- Speaking of database stuff, there was a performance-related update for the [indexes that we used in DSpace 5](https://github.com/DSpace/DSpace/pull/1791/)
  - We might want to [apply it in DSpace 6](https://github.com/DSpace/DSpace/pull/1792), as it was never merged to 6.x, but it helped with the performance of `/submissions` in XMLUI for us in [2018-03]({{< relref path="2018-03.md" >}})

## 2020-02-04

- The indexing issue I was having yesterday seems to only present itself the first time a new installation is running DSpace 6
  - Once the indexing induced by touching `dspace/solr/search/conf/reindex.flag` has finished, subsequent manual invocations of `dspace index-discovery -b` work as expected
  - Nevertheless, I sent a message to the dspace-tech mailing list describing the issue to see if anyone has any comments
- I am seeing that the number of important commits on the unreleased DSpace 6.4 are really numerous and it might be better for us to target that version
  - I did a simple test and it's easy to rebase my current 6.3 branch on top of the upstream `dspace-6_x` branch:

```
$ git checkout -b 6_x-dev64 6_x-dev
$ git rebase -i upstream/dspace-6_x
```

- I finally understand why our themes show all the "Browse by" buttons on community and collection pages in DSpace 6.x
  - The code in `./dspace-xmlui/src/main/java/org/dspace/app/xmlui/aspect/browseArtifacts/CommunityBrowse.java` iterates over all the browse indexes and prints them when it is called
  - The XMLUI theme code in `dspace/modules/xmlui-mirage2/src/main/webapp/themes/0_CGIAR/xsl/preprocess/browse.xsl` calls the template because the id of the div matches "aspect.browseArtifacts.CommunityBrowse.list.community-browse"
  - I checked the DRI of a community page on my local 6.x and DSpace Test 5.x by appending `?XML` to the URL and I see the ID is missing on DSpace 5.x
  - The issue is the same with the ordering of the "My Account" link, but in Navigation.java
  - I tried modifying `preprocess/browse.xsl` but it always ends up printing some default list of browse by links...
  - I'm starting to wonder if Atmire's modules somehow override this, as I don't see how `CommunityBrowse.java` can behave like ours on DSpace 5.x unless they have overridden it (as the open source code is the same in 5.x and 6.x)
  - At least the "account" link in the sidebar is overridden in our 5.x branch because Atmire copied a modified `Navigation.java` to the local xmlui modules folder... so that explains that (and it's easy to replicate in 6.x)

## 2020-02-05

- UptimeRobot told me that AReS Explorer crashed last night, so I logged into it, ran all updates, and rebooted it
- Testing Discovery indexing speed on my local DSpace 6.3:

```
$ time schedtool -D -e ~/dspace63/bin/dspace index-discovery -b
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  3771.78s user 93.63s system 41% cpu 2:34:19.53 total
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  3360.28s user 82.63s system 38% cpu 2:30:22.07 total
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  4678.72s user 138.87s system 42% cpu 3:08:35.72 total
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  3334.19s user 86.54s system 35% cpu 2:41:56.73 total
```

- DSpace 5.8 was taking about 1 hour (or less on this laptop), so this is 2-3 times longer!

```
$ time schedtool -D -e ~/dspace/bin/dspace index-discovery -b
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  299.53s user 69.67s system 20% cpu 30:34.47 total
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  270.31s user 69.88s system 19% cpu 29:01.38 total
```

- Checking out the DSpace 6.x REST API query client
  - There is a [tutorial](https://terrywbrady.github.io/restReportTutorial/intro) that explains how it works and I see it is very powerful because you can export a CSV of results in order to fix and re-upload them with batch import!
  - Custom queries can be added in `dspace-rest/src/main/webapp/static/reports/restQueryReport.js`
- I noticed two new bots in the logs with the following user agents:
  - `Jersey/2.6 (HttpUrlConnection 1.8.0_152)`
  - `magpie-crawler/1.1 (U; Linux amd64; en-GB; +http://www.brandwatch.net)`
- I filed an [issue to add Jersey to the COUNTER-Robots](https://github.com/atmire/COUNTER-Robots/issues/30) list
- Peter noticed that the statlets on community, collection, and item pages aren't working on CGSpace
  - I thought it might be related to the fact that the yearly sharding didn't complete successfully this year so the `statistics-2019` core is empty
  - I removed the `statistics-2019` core and had to restart Tomcat like six times before all cores would load properly (ugh!!!!)
  - After that the statlets were working properly...
- Run all system updates on DSpace Test (linode19) and restart it

## 2020-02-06

- I sent a mail to the dspace-tech mailing list asking about slow Discovery indexing speed in DSpace 6
- I destroyed my PostgreSQL 9.6 containers and re-created them using PostgreSQL 10 to see if there are any speedups with DSpace 6.x:

```
$ podman pull postgres:10-alpine
$ podman run --name dspacedb10 -v dspacedb_data:/var/lib/postgresql/data -e POSTGRES_PASSWORD=postgres -p 5432:5432 -d postgres:10-alpine
$ createuser -h localhost -U postgres --pwprompt dspacetest
$ createdb -h localhost -U postgres -O dspacetest --encoding=UNICODE dspacetest
$ createdb -h localhost -U postgres -O dspacetest --encoding=UNICODE dspace63
$ psql -h localhost -U postgres -c 'alter user dspacetest superuser;'
$ pg_restore -h localhost -U postgres -d dspacetest -O --role=dspacetest -h localhost ~/Downloads/cgspace_2020-02-06.backup
$ pg_restore -h localhost -U postgres -d dspace63 -O --role=dspacetest -h localhost ~/Downloads/cgspace_2020-02-06.backup
$ psql -h localhost -U postgres -f ~/src/git/DSpace/dspace/etc/postgres/update-sequences.sql dspacetest
$ psql -h localhost -U postgres -f ~/src/git/DSpace/dspace/etc/postgres/update-sequences.sql dspace63
$ psql -h localhost -U postgres -c 'alter user dspacetest nosuperuser;'
$ psql -h localhost -U postgres dspace63                               
dspace63=# CREATE EXTENSION pgcrypto;
dspace63=# DELETE FROM schema_version WHERE version IN ('5.0.2015.01.27', '5.6.2015.12.03.2', '5.6.2016.08.08', '5.0.2017.04.28', '5.0.2017.09.25', '5.8.2015.12.03.3');
dspace63=# DROP VIEW eperson_metadata;
dspace63=# \q
```

- I purged ~33,000 hits from the "Jersey/2.6" bot in CGSpace's statistics using my `check-spider-hits.sh` script:

```
$ ./check-spider-hits.sh -d -p -f /tmp/jersey -s statistics -u http://localhost:8081/solr
$ for year in 2018 2017 2016 2015; do ./check-spider-hits.sh -d -p -f /tmp/jersey -s "statistics-${year}" -u http://localhost:8081/solr; done
```

- I noticed another user agen in the logs that we should add to the list:

```
ReactorNetty/0.9.2.RELEASE
```

- I made [an issue on the COUNTER-Robots repository](https://github.com/atmire/COUNTER-Robots/issues/31)
- I found a [nice tool for exporting and importing Solr records](https://github.com/freedev/solr-import-export-json) and it seems to workfor exporting our 2019 stats from the large statistics core!

```
$ ./run.sh -s http://localhost:8081/solr/statistics -a export -o /tmp/statistics-2019-01.json -f 'dateYearMonth:2019-01' -k uid
$ ls -lh /tmp/statistics-2019-01.json
-rw-rw-r-- 1 aorth aorth 3.7G Feb  6 09:26 /tmp/statistics-2019-01.json
```

- Then I tested importing this by creating a new core in my development environment:

```
$ curl 'http://localhost:8080/solr/admin/cores?action=CREATE&name=statistics-2019&instanceDir=/home/aorth/dspace/solr/statistics&dataDir=/home/aorth/dspace/solr/statistics-2019/data'
$ ./run.sh -s http://localhost:8080/solr/statistics-2019 -a import -o ~/Downloads/statistics-2019-01.json -k uid
```

- This imports the records into the core, but DSpace can't see them, and when I restart Tomcat the core is not seen by Solr...
- I got the core to load by adding it to `dspace/solr/solr.xml` manually, ie:

```
  <cores adminPath="/admin/cores">
  ...
    <core name="statistics" instanceDir="statistics" />
    <core name="statistics-2019" instanceDir="statistics">
        <property name="dataDir" value="/home/aorth/dspace/solr/statistics-2019/data" />
    </core>
  ...
  </cores>
```

- But I don't like having to do that... why doesn't it load automatically?
- I sent a mail to the dspace-tech mailing list to ask about it
- Just for fun I tried to load these stats into a Solr 7.7.2 instance using the DSpace 7 solr config:
- First, create a Solr statistics core using the DSpace 7 config:
```
$ ./bin/solr create_core -c statistics -d ~/src/git/DSpace/dspace/solr/statistics/conf -p 8983
```

- Then try to import the stats, skipping a shitload of fields that are apparently added to our Solr statistics by Atmire modules:

```
$ ./run.sh -s http://localhost:8983/solr/statistics -a import -o ~/Downloads/statistics-2019-01.json -k uid -S author_mtdt,author_mtdt_search,iso_mtdt_search,iso_mtdt,subject_mtdt,subject_mtdt_search,containerCollection,containerCommunity,containerItem,countryCode_ngram,countryCode_search,cua_version,dateYear,dateYearMonth,geoipcountrycode,ip_ngram,ip_search,isArchived,isInternal,isWithdrawn,containerBitstream,file_id,referrer_ngram,referrer_search,userAgent_ngram,userAgent_search,version_id,complete_query,complete_query_search,filterquery,ngram_query_search,ngram_simplequery_search,simple_query,simple_query_search,range,rangeDescription,rangeDescription_ngram,rangeDescription_search,range_ngram,range_search,actingGroupId,actorMemberGroupId,bitstreamCount,solr_update_time_stamp,bitstreamId
```

- OK that imported! I wonder if it works... maybe I'll try another day

## 2020-02-07

- I did some investigation into DSpace indexing performance using flame graphs
  - Excellent introduction: http://www.brendangregg.com/flamegraphs.html
  - Using flame graphs with java: https://netflixtechblog.com/java-in-flames-e763b3d32166
  - Fantastic wrapper scripts for doing perf on Java processes: https://github.com/jvm-profiling-tools/perf-map-agent

```
$ cd ~/src/git/perf-map-agent
$ cmake     .
$ make
$ ./bin/create-links-in ~/.local/bin
$ export FLAMEGRAPH_DIR=/home/aorth/src/git/FlameGraph
$ export JAVA_HOME=/usr/lib/jvm/java-8-openjdk
$ export JAVA_OPTS="-XX:+PreserveFramePointer"
$ ~/dspace63/bin/dspace index-discovery -b &
# pid of tomcat java process
$ perf-java-flames 4478
# pid of java indexing process
$ perf-java-flames 11359
```

- All Java processes need to have `-XX:+PreserveFramePointer` if you want to trace their methods
- I did the same tests against DSpace 5.8 and 6.4-SNAPSHOT's CLI indexing process and Tomcat process
  - For what it's worth, it appears all the Hibernate stuff is in the CLI processes, so we don't need to trace the Tomcat process
- Here is the flame graph for DSpace 5.8's `dspace index-discovery -b` java process:

![DSpace 5.8 index-discovery flame graph](/cgspace-notes/2020/02/flamegraph-java-cli-dspace58.svg)

- Here is the flame graph for DSpace 6.4-SNAPSHOT's `dspace index-discovery -b` java process:

![DSpace 6.4-SNAPSHOT index-discovery flame graph](/cgspace-notes/2020/02/flamegraph-java-cli-dspace64-snapshot.svg)

- If the width of the stacks indicates time, then it's clear that Hibernate takes longer...
- Apparently there is a "flame diff" tool, I wonder if we can use that to compare!

## 2020-02-09

- This weekend I did a lot more testing of indexing performance with our DSpace 5.8 branch, vanilla DSpace 5.10, and vanilla DSpace 6.4-SNAPSHOT:

```
# CGSpace 5.8
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  385.72s user 131.16s system 19% cpu 43:21.18 total
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  382.95s user 127.31s system 20% cpu 42:10.07 total
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  368.56s user 143.97s system 20% cpu 42:22.66 total
schedtool -D -e ~/dspace/bin/dspace index-discovery -b  360.09s user 104.03s system 19% cpu 39:24.41 total

# Vanilla DSpace 5.10
schedtool -D -e ~/dspace510/bin/dspace index-discovery -b  236.19s user 59.70s system 3% cpu 2:03:31.14 total
schedtool -D -e ~/dspace510/bin/dspace index-discovery -b  232.41s user 50.38s system 3% cpu 2:04:16.00 total

# Vanilla DSpace 6.4-SNAPSHOT
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  5112.96s user 127.80s system 40% cpu 3:36:53.98 total
schedtool -D -e ~/dspace63/bin/dspace index-discovery -b  5112.96s user 127.80s system 40% cpu 3:21:0.0 total
```

- I generated better flame graphs for the DSpace indexing process by using `perf-record-stack` and filtering out the java process:

```
$ export JAVA_HOME=/usr/lib/jvm/java-8-openjdk
$ export PERF_RECORD_SECONDS=60
$ export JAVA_OPTS="-XX:+PreserveFramePointer"
$ time schedtool -D -e ~/dspace/bin/dspace index-discovery -b &
# process id of java indexing process (not Tomcat)
$ perf-java-record-stack 169639
$ sudo perf script -i /tmp/perf-169639.data > out.dspace510-1
$ cat out.dspace510-1 | ../FlameGraph/stackcollapse-perf.pl | grep -E '^java' | ../FlameGraph/flamegraph.pl --color=java --hash > out.dspace510-1.svg
```
- All data recorded on my laptop with the same kernel, same boot, etc.
- CGSpace 5.8 (with Atmire patches):

![DSpace 5.8 (with Atmire modules) index-discovery flame graph](/cgspace-notes/2020/02/out.dspace58-2.svg)

- Vanilla DSpace 5.10:

![Vanilla DSpace 5.10 index-discovery flame graph](/cgspace-notes/2020/02/out.dspace510-3.svg)

- Vanilla DSpace 6.4-SNAPSHOT:

![Vanilla DSpace 6.4-SNAPSHOT index-discovery flame graph](/cgspace-notes/2020/02/out.dspace64-3.svg)

- I sent my feedback to the dspace-tech mailing list so someone can hopefully comment.

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