SUSE/saptune

package note

import (
    "github.com/SUSE/saptune/system"
    "strconv"
    "strings"
)

// section [pagecache]

// GetPagecacheVal initialise the pagecache structure with the current
// system settings
func GetPagecacheVal(key string, cur *LinuxPagingImprovements) string {
    val := ""
    currentPagecache, err := LinuxPagingImprovements{PagingConfig: cur.PagingConfig}.Initialise()
    if err != nil {
        return ""
    }
    current := currentPagecache.(LinuxPagingImprovements)

    switch key {
    case "ENABLE_PAGECACHE_LIMIT":
        if current.VMPagecacheLimitMB == 0 {
            val = "no"
        } else {
            val = "yes"
        }
    case system.SysctlPagecacheLimitIgnoreDirty:
        val = strconv.Itoa(current.VMPagecacheLimitIgnoreDirty)
    case "OVERRIDE_PAGECACHE_LIMIT_MB":
        if current.VMPagecacheLimitMB == 0 {
            val = ""
        } else {
            val = strconv.FormatUint(current.VMPagecacheLimitMB, 10)
        }
    }
    *cur = current
    return val
}

// OptPagecacheVal optimises the pagecache structure with the settings
// from the configuration file or with a calculation
func OptPagecacheVal(key, cfgval string, cur *LinuxPagingImprovements) string {
    val := strings.ToLower(cfgval)

    switch key {
    case "ENABLE_PAGECACHE_LIMIT":
        if val != "yes" && val != "no" {
            system.WarningLog("wrong selection for ENABLE_PAGECACHE_LIMIT. Now set to default 'no'")
            val = "no"
        }
    case system.SysctlPagecacheLimitIgnoreDirty:
        if val != "2" && val != "1" && val != "0" {
            system.WarningLog("wrong selection for %s. Now set to default '1'", system.SysctlPagecacheLimitIgnoreDirty)
            val = "1"
        }
        cur.VMPagecacheLimitIgnoreDirty, _ = strconv.Atoi(val)
    case "OVERRIDE_PAGECACHE_LIMIT_MB":
        opt, _ := cur.Optimise()
        if opt == nil {
            _ = system.ErrorLog("page cache optimise had problems reading the Note definition file '%s'. Please check", cur.PagingConfig)
            return ""
        }
        optval := opt.(LinuxPagingImprovements).VMPagecacheLimitMB
        if optval != 0 {
            cur.VMPagecacheLimitMB = optval
            val = strconv.FormatUint(optval, 10)
        } else {
            cur.VMPagecacheLimitMB = 0
            val = ""
        }
    }

    return val
}

// SetPagecacheVal applies the settings to the system
func SetPagecacheVal(key string, cur *LinuxPagingImprovements) error {
    var err error
    if key == "OVERRIDE_PAGECACHE_LIMIT_MB" {
        err = cur.Apply()
    }
    return err
}