DBSIZE takes time in minutes and keyspace info missing when SSD storage tier is enabled

Describe the bug

When running Garnet v1.0.87 with SSD storage tier enabled, the DBSIZE command becomes extremely slow (5-10 minutes) after loading data. Additionally, the INFO command does not show any keyspace section, even though keys exist in SSD tier.

• This issue is consistently reproducible.

Steps to reproduce the bug

1. Start Garnet on a GCP C4D-HighMem-64 machine with the following configuration:

{
  "Port": 6379,
  "Address": "0.0.0.0",
  "MemorySize": "16g",
  "PageSize": "32m",
  "SegmentSize": "4g",
  "IndexSize": "16g",
  "IndexMaxSize": "64g",
  "IndexResizeFrequencySecs": 30,
  "IndexResizeThreshold": 65,
  "EnableReadCache": true,
  "ReadCacheMemorySize": "420g",
  "ReadCachePageSize": "2m",
  "DisableObjects": true,
  "EnableStorageTier": true,
  "LogDir": "/mnt/localssd/garnet/log",
  "CheckpointDir": "/mnt/localssd/garnet/ckpt",
  "Recover": true,
  "EnableAOF": false,
  "CompactionFrequencySecs": 0,
  "LogLevel": "Information",
  "MetricsSamplingFrequency": 10
}

2. Load ~1.2 GB of data into the SSD tier using:

docker run --rm \
  --cpus="$(nproc)" \
  --memory="$(free -m | awk '/^Mem:/{print int($2*0.95)"m"}')" \
  --network host \
  redislabs/memtier_benchmark:latest \
  -d 256000 \
  --distinct-client-seed \
  -h <garnet_host> \
  --ratio 1:0 \
  --key-maximum 300000000 \
  -c 15 -t "$(nproc)" \
  --test-time 1000

3. After load is complete:
   • Run DBSIZE → takes 5-10 minutes
   • Run INFO → keyspace section is missing

Expected behavior

• DBSIZE should return quickly without long blocking durations.
• INFO should display keyspace details even when keys are stored in SSD tier.

Screenshots

Release version

v1.0.87

IDE

N/A (server-side issue)

OS version

Ubuntu 24.04.3 LTS

Additional context

No response