add blob comment for conf/pika.conf

conf/pika.conf

@@ -326,8 +326,11 @@ max-bytes-for-level-multiplier : 10
 # rate limiter bandwidth, default 200MB
 #rate-limiter-bandwidth : 209715200
 
+###########################
 # rocksdb blob configure
 # wiki https://github.com/facebook/rocksdb/wiki/BlobDB
+###########################
+
 # enable rocksdb blob, default no
 # enable-blob-files : yes
 
@@ -341,10 +344,12 @@ max-bytes-for-level-multiplier : 10
 
 # the compression type to use for blob files. All blobs in the same file are compressed using the same algorithm.
 # Supported types: [snappy, zlib, lz4, zstd]. If you do not wanna compress the SST file, please set its value as none.
+# [NOTICE] The Pika official binary release just link the snappy library statically, which means that
 # you should compile the Pika from the source code and then link it with other compression algorithm library statically by yourself.
 # blob-compression-type : lz4
 
 # set this to open to make BlobDB actively relocate valid blobs from the oldest blob files as they are encountered during compaction.
+# The value option is [yes | no]
 # enable-blob-garbage-collection : no
 
 # the cutoff that the GC logic uses to determine which blob files should be considered “old“.
@@ -360,4 +365,5 @@ max-bytes-for-level-multiplier : 10
 
 # blob-num-shard-bits default -1, the number of bits from cache keys to be use as shard id.
 # The cache will be sharded into 2^blob-num-shard-bits shards.
-# blob-num-shard-bits : -1
+# blob-num-shard-bits : -1
+