Flesh out the benchmark post some more

content/ceph-benchmarking/index.md

@@ -1,6 +1,6 @@
 +++
 title = "Ceph Benchmarking"
-date = 2026-03-01
+date = 2026-02-21
 description = "The results of some of my recent ceph benchmarks"
 draft = true
 
@@ -9,6 +9,9 @@ categories = ["Homelab"]
 tags = ["Homelab", "Ceph"]
 +++
 
+## Motivation
+I have been running a ceph cluster in my homelab for about 2 years now, but never properly benchmarked it, let alone wrote down my findings or any potential conclusions.
+
 ## Setup everything for the Benchmarking
 On a machine in the ceph-cluster already:
 1. Generate a minimal ceph config using `ceph config generate-minimal-conf`
@@ -39,33 +42,100 @@ Setup the benchmark itself:
 5. `mount /dev/rbd0 /mnt/bench`
 
 ## Benchmarks
+All benchmarks are run with the same configuration, only changing the access (read/write, random/sequential).
+Key configuration options are:
+- using libaio
+- direct io
+- 1 job
 
+{% details(summary="fio config") %}
+```
+[global]
+ioengine=libaio
+direct=1
+size=4G
+numjobs=1
+runtime=60s
+time_based
+startdelay=5s
+group_reporting
+stonewall
+
+name=write
+rw=write
+filename=bench
+
+[1io_4k]
+iodepth=1
+bs=4k
+[1io_8k]
+iodepth=1
+bs=8k
+[1io_64k]
+iodepth=1
+bs=64k
+[1io_4M]
+iodepth=1
+bs=4M
+
+[32io_4k]
+iodepth=32
+bs=4k
+[32io_8k]
+iodepth=32
+bs=8k
+[32io_64k]
+iodepth=32
+bs=64k
+[32io_4M]
+iodepth=32
+bs=4M
+```
+{% end %}
 
 ## Results
-{% details(summary="Random Reads - 1 Job") %}
+{% details(summary="Random Reads") %}
 {{ fio_benchmark(path="content/ceph-benchmarking/benchmarks/random_read.json") }}
 {% end %}
 
-{% details(summary="Random Writes - 1 Job") %}
+{% details(summary="Random Writes") %}
 {{ fio_benchmark(path="content/ceph-benchmarking/benchmarks/random_write.json") }}
 {% end %}
 
-{% details(summary="Sequential Reads - 1 Job") %}
+{% details(summary="Sequential Reads") %}
 {{ fio_benchmark(path="content/ceph-benchmarking/benchmarks/seq_read.json") }}
 {% end %}
 
-{% details(summary="Sequential Writes - 1 Job") %}
+{% details(summary="Sequential Writes") %}
 {{ fio_benchmark(path="content/ceph-benchmarking/benchmarks/seq_write.json") }}
 {% end %}
 
-## TODO
-- Try directly on the block device
-- Try this using xfs instead of ext4
-- Try this with and without drive caches
+## Conclusion
+1. Overall I am satisfied with the performance of the cluster for my current use-case.
+2. There is a lot of room for improvement in the low queue-depth range
+3. The network is not really a limiting factor currently
+    - None of the nodes in the cluster exceeded 500MiB/s of TX or RX, so there is plenty of room for growth
+    - My client used for testing was limited by the network, evident by the fact that the highest speed achieved is ~1.2GB/s (~10Gb/s)
+4. My smallest node (the embedded epyc) could be the limiting factor as in some benchmarks, it reached 100% cpu usage, while my other nodes never exceeded 40%
 
+## Extra Details
+{% details(summary="Cluster Hardware") %}
+- 10 Gb Networking between all nodes
+- Node
+    - Ryzen 5 5500
+    - 64GB RAM
+    - 4x 480GB enterprise SSD
+- Node
+    - Ryzen 5 3600
+    - 64GB RAM
+    - 4x 480GB enterprise SSD
+- Node
+    - EPYC 3151
+    - 64GB RAM
+    - 4x 480GB enterprise SSD
+{% end %}
 
-## Details
-{% details(summary="Command to convert raw data into vis data") %}
+{% details(summary="Command to convert raw data into data for visualisation") %}
 
 ```bash
 jq '[.jobs[] | { iodepth: ."job options".iodepth, bs: ."job options".bs, operations: { iops: .write.iops, bw_bytes: .write.bw_bytes } }]' content/ceph-benchmarking/benchmarks/raw_random_write.json | jq '
@@ -96,3 +166,8 @@ jq '[.jobs[] | { iodepth: ."job options".iodepth, bs: ."job options".bs, operati
 '
 ```
 {% end %}
+
+## Future Work
+- Try directly on the block device
+- Try this using xfs instead of ext4
+- Try this with and without drive caches