[pve-devel] [PATCH zfsonlinux] arcstat/arc_summary: workaround for stats only present with cache device

[pve-devel] [PATCH zfsonlinux] arcstat/arc_summary: workaround for stats only present with cache device

[Stoiko Ivanov]

This commit updates Thomas' patch to deal with a 2.0 kernel module
with 2.1 arc_summary/arcstat

Tested by adding a cache-device to a zpool and running both commands
to verify no KeyError exception is thrown.

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
---
I hope the fixup in the patch and commit-log above my S-o-b tag is ok
- else feel free to adapt (can also gladly resend)

 ...-guard-access-to-l2arc-MFU-MRU-stats.patch | 63 +++++++++++++++++--
 1 file changed, 58 insertions(+), 5 deletions(-)

diff --git a/debian/patches/0011-arc-stat-summary-guard-access-to-l2arc-MFU-MRU-stats.patch b/debian/patches/0011-arc-stat-summary-guard-access-to-l2arc-MFU-MRU-stats.patch
index ead0943c..6a704848 100644
--- a/debian/patches/0011-arc-stat-summary-guard-access-to-l2arc-MFU-MRU-stats.patch
+++ b/debian/patches/0011-arc-stat-summary-guard-access-to-l2arc-MFU-MRU-stats.patch
@@ -15,13 +15,18 @@ should be better to show some possible wrong data for new stat-keys
 than throwing an exception.
 
 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
+
+also move l2_mfu_asize  l2_mru_asize l2_prefetch_asize
+l2_bufc_data_asize l2_bufc_metadata_asize to .get accessor
+(these are only present with a cache device in the pool)
+Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
 ---
- cmd/arc_summary/arc_summary3 | 8 ++++----
- cmd/arcstat/arcstat.in       | 4 ++--
- 2 files changed, 6 insertions(+), 6 deletions(-)
+ cmd/arc_summary/arc_summary3 | 28 ++++++++++++++--------------
+ cmd/arcstat/arcstat.in       | 14 +++++++-------
+ 2 files changed, 21 insertions(+), 21 deletions(-)
 
 diff --git a/cmd/arc_summary/arc_summary3 b/cmd/arc_summary/arc_summary3
-index 7b28012ed..0a81b2bc7 100755
+index 7b28012ed..fe6a6d9e2 100755
 --- a/cmd/arc_summary/arc_summary3
 +++ b/cmd/arc_summary/arc_summary3
 @@ -617,13 +617,13 @@ def section_arc(kstats_dict):
@@ -42,8 +47,39 @@ index 7b28012ed..0a81b2bc7 100755
      prt_i1('L2 ineligible evictions:',
             f_bytes(arc_stats['evict_l2_ineligible']))
      print()
+@@ -765,20 +765,20 @@ def section_l2arc(kstats_dict):
+            f_perc(arc_stats['l2_hdr_size'], arc_stats['l2_size']),
+            f_bytes(arc_stats['l2_hdr_size']))
+     prt_i2('MFU allocated size:',
+-           f_perc(arc_stats['l2_mfu_asize'], arc_stats['l2_asize']),
+-           f_bytes(arc_stats['l2_mfu_asize']))
++           f_perc(arc_stats.get('l2_mfu_asize', 0), arc_stats['l2_asize']),
++           f_bytes(arc_stats.get('l2_mfu_asize', 0))) # 2.0 module compat
+     prt_i2('MRU allocated size:',
+-           f_perc(arc_stats['l2_mru_asize'], arc_stats['l2_asize']),
+-           f_bytes(arc_stats['l2_mru_asize']))
++           f_perc(arc_stats.get('l2_mru_asize', 0), arc_stats['l2_asize']),
++           f_bytes(arc_stats.get('l2_mru_asize', 0))) # 2.0 module compat
+     prt_i2('Prefetch allocated size:',
+-           f_perc(arc_stats['l2_prefetch_asize'], arc_stats['l2_asize']),
+-           f_bytes(arc_stats['l2_prefetch_asize']))
++           f_perc(arc_stats.get('l2_prefetch_asize', 0), arc_stats['l2_asize']),
++           f_bytes(arc_stats.get('l2_prefetch_asize',0))) # 2.0 module compat
+     prt_i2('Data (buffer content) allocated size:',
+-           f_perc(arc_stats['l2_bufc_data_asize'], arc_stats['l2_asize']),
+-           f_bytes(arc_stats['l2_bufc_data_asize']))
++           f_perc(arc_stats.get('l2_bufc_data_asize', 0), arc_stats['l2_asize']),
++           f_bytes(arc_stats.get('l2_bufc_data_asize', 0))) # 2.0 module compat
+     prt_i2('Metadata (buffer content) allocated size:',
+-           f_perc(arc_stats['l2_bufc_metadata_asize'], arc_stats['l2_asize']),
+-           f_bytes(arc_stats['l2_bufc_metadata_asize']))
++           f_perc(arc_stats.get('l2_bufc_metadata_asize', 0), arc_stats['l2_asize']),
++           f_bytes(arc_stats.get('l2_bufc_metadata_asize', 0))) # 2.0 module compat
+ 
+     print()
+     prt_1('L2ARC breakdown:', f_hits(l2_access_total))
 diff --git a/cmd/arcstat/arcstat.in b/cmd/arcstat/arcstat.in
-index cd9a803a2..6878419e7 100755
+index cd9a803a2..ea45dc602 100755
 --- a/cmd/arcstat/arcstat.in
 +++ b/cmd/arcstat/arcstat.in
 @@ -482,8 +482,8 @@ def calculate():
@@ -57,3 +93,20 @@ index cd9a803a2..6878419e7 100755
      v["el2inel"] = d["evict_l2_ineligible"] // sint
      v["mtxmis"] = d["mutex_miss"] // sint
  
+@@ -498,11 +498,11 @@ def calculate():
+         v["l2size"] = cur["l2_size"]
+         v["l2bytes"] = d["l2_read_bytes"] // sint
+ 
+-        v["l2pref"] = cur["l2_prefetch_asize"]
+-        v["l2mfu"] = cur["l2_mfu_asize"]
+-        v["l2mru"] = cur["l2_mru_asize"]
+-        v["l2data"] = cur["l2_bufc_data_asize"]
+-        v["l2meta"] = cur["l2_bufc_metadata_asize"]
++        v["l2pref"] = cur.get("l2_prefetch_asize", 0)
++        v["l2mfu"] = cur.get("l2_mfu_asize", 0)
++        v["l2mru"] = cur.get("l2_mru_asize", 0)
++        v["l2data"] = cur.get("l2_bufc_data_asize", 0)
++        v["l2meta"] = cur.get("l2_bufc_metadata_asize", 0)
+         v["l2pref%"] = 100 * v["l2pref"] // v["l2asize"]
+         v["l2mfu%"] = 100 * v["l2mfu"] // v["l2asize"]
+         v["l2mru%"] = 100 * v["l2mru"] // v["l2asize"]
-- 
2.30.2

[pve-devel] applied: [PATCH zfsonlinux] arcstat/arc_summary: workaround for stats only present with cache device

[Thomas Lamprecht]

On 11.11.21 18:17, Stoiko Ivanov wrote:
> This commit updates Thomas' patch to deal with a 2.0 kernel module
> with 2.1 arc_summary/arcstat
> 
> Tested by adding a cache-device to a zpool and running both commands
> to verify no KeyError exception is thrown.
> 
> Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
> ---
> I hope the fixup in the patch and commit-log above my S-o-b tag is ok
> - else feel free to adapt (can also gladly resend)

top-notch! 

>  ...-guard-access-to-l2arc-MFU-MRU-stats.patch | 63 +++++++++++++++++--
>  1 file changed, 58 insertions(+), 5 deletions(-)
> 
>

applied, thanks!