ArcGIS10缓存新特性

<p style="BORDER-BOTTOM-STYLE: none; TEXT-ALIGN: left; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; WIDOWS: 2; TEXT-TRANSFORM: none; BACKGROUND-COLOR: rgb(255,255,255); TEXT-INDENT: 0px; MARGIN: 0px="0px"  auto="auto"  12px; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT: 14px="14px" /23px Arial, sans-serif; WORD-WRAP: break-word; WHITE-SPACE: normal; ORPHANS: 2; BORDER-TOP-STYLE: none; LETTER-SPACING: normal; COLOR: rgb(51,51,51); BORDER-LEFT-STYLE: none; WORD-SPACING: 0px; PADDING-TOP: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px">arcgis server10引入了新的缓存格式Compact，以前的图片格式命名为Exploded ，两种缓存格式是可选的。新的缓存格式可以使服务更容易迁移。以下是esri官方网站对Compact格式的描述：<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>Compact is the new format. It actually does not zip or compress the tiles in any way; rather, it groups the tiles together in large files called bundles. A single bundle can hold up to about 16,000 tiles. The result is a cache with dozens or hundreds of files, instead of thousands or millions. This speeds copying immensely, and is especially useful in workflows where you use a staging server to create tiles, then move the tiles to a production server.</p>
<p style="BORDER-BOTTOM-STYLE: none; TEXT-ALIGN: left; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; WIDOWS: 2; TEXT-TRANSFORM: none; BACKGROUND-COLOR: rgb(255,255,255); TEXT-INDENT: 0px; MARGIN: 0px="0px"  auto="auto"  12px; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT: 14px="14px" /23px Arial, sans-serif; WORD-WRAP: break-word; WHITE-SPACE: normal; ORPHANS: 2; BORDER-TOP-STYLE: none; LETTER-SPACING: normal; COLOR: rgb(51,51,51); BORDER-LEFT-STYLE: none; WORD-SPACING: 0px; PADDING-TOP: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px">The compact storage format also yields a smaller cache. Have you ever looked at a pre-ArcGIS Server 10 cache and noticed a discrepancy between “Size” and “Size on Disk”? This is because the smallest size that Windows can use to store a file is 4k by default. Unless you've changed the default format of your disk, any tile that's less than 4k is going to waste space. That wasted space adds up when you have thousands of small tiles. With the compact format, you get a cache where the Size and Size on Disk are essentially the same because you are storing the data in large continuous streams.<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>Exploded是以前的缓存格式，它是使用图片的方式存储来单独存储每个title，这样一幅地图会出现很多个title。Windows下默认一个文件占用磁盘空间最小为4k，不足4k的也需要占用4k的空间，这样一来，大量的title会造成磁盘空间的浪费。同时，大量的title会给迁移带来麻烦，不得不耐心等待title的拷贝。<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>Compact格式能够很好的弥补Exploded的不足。Compact是一种紧凑型的缓存格式，它把title拼装为更大的hundreds文件格式，而每个hundreds文件最多存放16000个title，这样，对于一个切片的地图服务来说，产生的title文件数目就会大大缩减，从而减少了磁盘空间的浪费。对于拷贝title来说，由于文件数量的大大减少，拷贝的速度也会大幅提升。<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>使用Compact格式的title，不能像以前那样通过title的URL直接访问title，ArcGIS的客户端和RESI API能够自动读取到Compact  hundreds的title，并将其在前段显示。但如果非得从虚拟目录下获取title，那就只能使用Exploded格式的缓存。<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/><a style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT-FAMILY: 宋体; BORDER-TOP-STYLE: none; COLOR: rgb(0,0,0); BORDER-LEFT-STYLE: none; TEXT-DECORATION: none; PADDING-TOP: 0px" href="http://www.gisall.com/batch.download.php?aid=1796" target="_blank"><img style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; MAX-WIDTH: 560px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px" border="0" alt="" src="http://www.gisall.com/attachments/2010/07/122747_201007220924231Y4em.jpg"/></a><br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/><a style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT-FAMILY: 宋体; BORDER-TOP-STYLE: none; COLOR: rgb(0,0,0); BORDER-LEFT-STYLE: none; TEXT-DECORATION: none; PADDING-TOP: 0px" href="http://www.gisall.com/batch.download.php?aid=1800" target="_blank"><img style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; MAX-WIDTH: 560px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px" border="0" alt="" src="http://www.gisall.com/attachments/2010/07/122747_201007220924421SvsH.jpg"/></a><br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>esri还提供专门工具对Compact和Exploded格式进行转换。在ArcToolBox的中提供了convert Map Server cache storage format 工具。<br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/><br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/><a style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT-FAMILY: 宋体; BORDER-TOP-STYLE: none; COLOR: rgb(0,0,0); BORDER-LEFT-STYLE: none; TEXT-DECORATION: none; PADDING-TOP: 0px" href="http://www.gisall.com/batch.download.php?aid=1798" target="_blank"><img style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; MAX-WIDTH: 560px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px" border="0" alt="" src="http://www.gisall.com/attachments/2010/07/122747_201007220924331qX1G.jpg"/></a><br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/>除此之外，server cache工具还新增了缓存导入/导出功能。用户可以按需要把某个区域的缓存导出进行分发，也可以把多个已经存在的缓存导入合并。<a style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT-FAMILY: 宋体; BORDER-TOP-STYLE: none; COLOR: rgb(0,0,0); BORDER-LEFT-STYLE: none; TEXT-DECORATION: none; PADDING-TOP: 0px" href="http://www.gisall.com/batch.download.php?aid=1797" target="_blank"><img style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; MAX-WIDTH: 560px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px" border="0" alt="" src="http://www.gisall.com/attachments/2010/07/122747_201007220924281o5gk.jpg"/></a><br style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px"/><a style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; FONT-FAMILY: 宋体; BORDER-TOP-STYLE: none; COLOR: rgb(0,0,0); BORDER-LEFT-STYLE: none; TEXT-DECORATION: none; PADDING-TOP: 0px" href="http://www.gisall.com/batch.download.php?aid=1799" target="_blank"><img style="BORDER-BOTTOM-STYLE: none; PADDING-BOTTOM: 0px; BORDER-RIGHT-STYLE: none; MARGIN: 0px="0px"  auto; PADDING-LEFT: 0px; PADDING-RIGHT: 0px; MAX-WIDTH: 560px; BORDER-TOP-STYLE: none; BORDER-LEFT-STYLE: none; PADDING-TOP: 0px" border="0" alt="" src="http://www.gisall.com/attachments/2010/07/122747_201007220924371KjDm.jpg"/></a></p>